Church becomes implicated in murder conspiracies when he goes undercover.
When a police officer is shot, Undercover are called to investigate the prime suspects within a Romanian gang.
When a serial killer claims a third victim, Undercover are called in to track him down.
The unit goes into damage control after Kaye's disappearance.
While undercover, Church becomes involved with Cameron Fraser, a brutal and highly skilled mercenary.
Stone goes undercover to crack a large-scale Ecstasy racket.
MacKenzie goes undercover to befriend a women capable of exposing a corrupt politician.
Working undercover, Church inadvertently becomes involved in a volatile siege situation instigated by three young delinquents.
Internal Affairs raids the Stingers warehouse after receiving a tip-off suggesting corruption. Bernie Rocca becomes the focus of the corruption allegation when he can't explain why some heroin is missing and why there is a spare $40,000 in his safe.
Church gives a long-term informant one last chance to prove his worth, while investigating a potential armoured car robbery.
Church goes undercover with a bikie gang suspected in producing counterfeit money.
After being shot at a drug deal, Stone remains undercover to crack a gun dealing racket. Mackenzie is concerned about the psychological effects the shooting may have on Stone and his future as an undercover operative.
The Unit goes undercover to locate a prison escapee and investigate claims that police want him dead, rather than recaptured.
Stone and Angie go undercover to infiltrate a radical environmental group suspected of stealing explosives to service terrorist activities; Church must overcome a personal vendetta.
Mac and Angie go undercover in a brothel following the murder of a second prostitute.
While investigating a murder, Church inadvertently becomes involved with a well known crime family.
As Church works to infiltrate a powerful crime family, he gets more involved than he had ever expected.
As the Unit slowly gains information to bring about the downfall of a powerful crime family, an unexpected development threatens their progress, and forces Church to remain undercover.
The Unit fears that Church's involvement with an influential crime family may cause him to cross the line, and betray them for a life of crime.
The Unit discovers that someone has information that could expose Church while he's undercover, and so begins a deadly race against time.
Stone and Angie go undercover to investigate a murder believed to be linked to a pornographic film industry. Meanwhile MacKenzie receives compromising photographs related to her past relationship with Church.
MacKenzie pushes Angie and Stone to solve the ongoing porn murder case, as the compromising photographs of herself and Church threaten the security of the Unit.
The undercover unit faces a dilemma when the life of Church's informant is threatened. Should they abort the sting?
Rocca finds himself in unfamiliar territory when he goes undercover with Church on a case involving gold smuggling, political intrigue, and attempted assassination.
Rocca goes undercover with Church on a case involving goldsmuggling, political intrigue and attempted assassination.
Mackenzie goes behind bars to investigate a murderer suspected of grand scale embezzlement.
The Unit work to protect a coin dealer they believe will be the target of a revenge attack.
The Unit discover there is a contract out on Church's life. Someone wants him silenced before he can testify.
Working closely with a psychological profiler, Mackenzie puts her life on the line to trap a serial killer who uses the internet to select his victims.
Working undercover in an explosives trading investigation, Stone allows his heart to rule his judgement, putting the operation and his life at risk.
During an undercover operation, Church is involved in a shooting accident which brings him under scrutiny from Internal Affairs.
Working undercover in the music industry, Angie's life spins out of control as she begins to question her future in Undercover.
When Stone becomes the target of a revenge attack, Angie and his family get caught in the crossfire.
Church must team up with a new recruit to investigate the abduction of the daughter of a Family Court judge.
Church uses unorthodox methods during a drug investigation when he discovers his nephew, Matt, caught up in the cycle of addiction.
The Unit investigate a series of truck hi-jackings that have led to murder.
Following a car bomb attack, Stone and Angie go undercover to investigate a radical right-wing group suspected of race terrorism.
When Church and Mackenzie team up to investigate an illegal adoption racket, Mackenzie's informant decides to take justice into his own hands.
A routine drug bust takes a sudden turn forcing Rocca to take the place of the target, while Church faces the challenge of a lifetime as he deals with a pregnant informant.
The unit become involved in a robbery and double murder when they go undercover to infiltrate a group of high-rolling gamblers using black money.
Church breaks all the rules when he goes after Rocca's attacker and ends up head to head with the new boss of Undercover.
The Final episode of the year for the Melbourne-based cop drama finds undercover operative Church caltivating a new informant. And this man's information is amazingly good. While the future of the undercover operation is under threat, Chruch has serveral meetings with his informant, Dingo. Finally, he extracts details with will enable the Singers group to bust a big-time drug ring. But there's a twist in the tale which makes this one of the most satisfying episodes of the series this year.
A sassy new operative arrives at the unit just as the group go undercover to entrap a group of young theives. But a mistake leads to a kidnapping, placing everyone in danger.
Church goes undercover in the world of stolen art, and must grapple with some of the conflicting emotions which have shaped his character and behaviour, when he discovers that the target abuses his son.
A well planned sting on a group of thieves intent on robbing a very large bank goes horribly wrong when the unit discover that the bank the group is robbing is in a completely different city... and state.
Angie's assignment is jeopardised with the unexpected arrival of her sister; and Mac is faced with a dilemma when she discovers that Danni's involved with an associate of an underworld heavy.
Danni's future at the unit is on the line when her ex-boyfriend becomes the prime suspect in a horse-doping scam.
Hollister asks Mac for help to capture the elusive Marty Stockwell, a master bank robber. He fatally shot one of Hollister's men, and now he wants revenge. So, Church and Danni go undercover to try and bring him to justice.
In court, things go horribly wrong when the Magistrate dismisses the charges against Tony Howarth for shooting Bernie Rocca.
Church becomes involved in a young boy's life after he catches him trying to steal his car, and uses him to uncover a car stealing racket. Meanwhile, Angie risks herself, and goes undercover to determine the truth about a dentist who takes advantage of his patients.
After three backpackers are murdered, Stone is sent in to investigate Evelyn Leigh, where his emotions almost cost his life.
Mac and Church must infiltrate a neighbourhood residents group who are protesting the acquittal and return to the neighbourhood of a local teacher recently charged with the murder of a young student.
When Church conducts a sting on a bikie gang, a simple gun deal becomes complicated when Church is hired to do a hit.
The undercover unit face a psychological challenge when an operative looses his identity during a long-term assignment.
Danni learns the meaning of betrayal when she is forced to use an innocent to solve a murder.
Mackenzie faces a dilemma when Detective Inspector Bill Hollister is revealed as a regular client at an illegal brothel which is the subject of a sting.
When Church strikes up an unlikely friendship with a hitman, after preventing him from killing himself, he is drawn into the middle of a heated triangle with no simple solution.
Danni's life is placed in danger when a well-known career criminal turns Crown witness under unusual circumstances.
Mackenzie's past comes back to haunt her when her adopted brother is released from prison.
Angie is stalked by an obsessed admirer as she works undercover to expose an armed robbery ring.
Church must put his career on the line when an old Academy buddy is implicated in a homicide.
A personal favour from Church becomes a case for Undercover when an illegal organ-trading scam is exposed.
The Undercover Unit are assigned to investigate a five-year-old unsolved bank robbery with tragic consequences.
Mackenzie and Angie face an Internal Affairs investigation when an informant suicides, while Stone faces some important issues about his future in undercover.
Mackenzie and Hollister are called to investigate a homicide at the docks. Church works undercover as a customs officer when the unit has been called in to investigate the deaths of 11 illegal immigrants found inside a shipping container.
Drastic measures are taken to allay the suspicions of a drug syndicate and win their confidence. Meanwhile, Mac has to decide whether to accept a romantic proposition.
With what is feared to be a serial killer at large, the Undercover Unit is asked to gather evidence on a man recently released from prison after serving time for assault.
Mackenzie and Church pose as a feuding couple, while investigating the disappearance of a man while visiting a health spa where couples go to heal their ailing marriages.
Moonlighting as a Private Eye for an old friend, Tom Barton, Church is labelled a suspect when Tom is found dead. Church ignores all warnings to stay well away from the case, and delves into the complicated world of Tom's clientele, learning a few secrets along the way.
Church goes undercover in a bike gang to bust them on drug dealings. However, when the unit realises, after a fight and a murder, that the gang is at war with another bike gang, the pressure is on Church to stop an all out bloodbath.
The future of the unit is brought into question following Oscar's shooting the biker gang leader. Internal Affairs leaves no stone unturned in its investigation of the incident, leaving Church to choose his loyalties when Mackenzie attempts to rally the entire unit together to save Oscar.
In the aftermath of Bill Hollister's murder, Church goes on a crusade to catch who he believes is responsible. Angie visits her sister only to discover a tragic secret, and Mackenzie grapples with her feelings and how to face Hollister's family.
Church and Danni pose as foster parents in an unusual operation to capture Australia's most wanted armed robber.
The Undercover Unit investigate a disturbing ring of criminals, who use an internet chat-room to procure their victims.
The Undercovers find themselves battling a race against time when called in to investigate an extortion attempt against a pharmaceutical company.
A geeky inventor is suspected of being involved in credit-card doctoring, internet fraud, and making bombs. When Church is undercover at his house, a raid is carried out by gunnmen he believes are cops. And the cops-against-cops scenario is complicated when it appears the fraud suspect was involved with the death of Bill Hollister, who died in a bomb blast. Meanwhile, Stone finds himself recruited to undertake the most daunting of tasks when he is hired as a sniper by a bent cop.
In a case that has personal resonance for Mackenzie, the Undercover Unit stage a intensive investigation, determined to nail Bill Hollister's murderer.
Danni's life and career is threatened when an escaped criminal seeks his revenge.
A case of mistaken identity results in Stone being recruited to assist with a major armed robbery.
Following a spate of violent robberies, Church and the others are placed undercover as taxi drivers, in hope of catching the offender in the act. Unlike the others, Church actually likes the job, and the stories people have to tell, and when he takes a fare from a highly agitated young man, he hears a story to beat all stories.
MacKenzie investigates a private detective who specialises in adoption cases with the secret hope of finding her birth mother.
Church tags an unconvicted robber/murderer in the hope that he will lead them to unrecovered bank funds, while Angie and Stone try to locate a missing accomplice. Meanwhile, MacKenzie has news on her birth mother.
The Unit works with an undercover operative from Queensland to defeat a gang of amphetamine dealers responsible for a kidnapping.
Stone is caught in a siege at a hospital when an armed robbery goes horribly wrong.
Church's worlds collide when he has to attend his 20 year high school reunion as part of a drug sting.
As Church, Danni, Stone and Angie focus on a drug sting, Mackenzie is distracted by an invitation to apply for Head of Homicide - which would mean leaving the Undercover Unit.
Mackenzie becomes the victim of a grifter on the eve of her interview for head of homicide, while Church finds his career threatened.
Angie faces one of her toughest cases yet when she has to develop a romantic relationship with a murder suspect and then coerce him into becoming an informant.
Danni's determination to go it alone with her pregnancy clouds her professional judgement when she stumbles across an illegal adoption racket.
Mackenzie discovers the grifter who drugged her is linked to a senior colleague - someone who has good reason to want her out of the running for head of Homocide.
Stone cultivates a live-wire young prostitute named Brittany to get information on a dangerous drug crime.
Church is sent undercover to share a cell with a convicted murderer.
Angie is forced to bend the rules as she attempts to prevent her sister Sam from being arrested on drug importation charges.
Danni has to protect and help prepare for the court appearance of former undercover cop Gary Edgerton, the reluctant key witness in the trial of a major criminal.
Stone investigates a woman who may just be organising a hit on her husband, while Mackenzie is dealing with hitmen of a different kind.
Angie and the rest of the Undercover Unit rally around Mackenzie, risking their jobs in order to prove her innocence.
With Harry Love in a position to make his final move against Mackenzie, she and the Undercover Unit are forced to take desperate action, with tragic consequences.
Undercover teams up with Armed Robbery to bust a violent robbery ring. Church infiltrates the group but is forced to bow out when he is given a shotgun and told to rob a convenience store. It looks like Undercover has blown it—until Angie uses her real-life romance with informant Marty Engle to gain access to the ring, a situation that places them both in dangerous territory.
Stone and Church go undercover to investigate a pair of teenage drug manufacturers, with unexpected tragic consequences.
Stone is abducted when Undercover's attempt to bust an international arms dealing ring, run by lethal ex SAS officers, fails.
When a failed drug bust leaves the Undercover Unit with a dead dealer high class prostitute holding a couple of bags of cocaine, the Unit undertake an operation inside a busy brothel: Gotham City.
When an undercover operation causes the death of a young woman, Church and Angie are faced with the dilemma of saving one dangerous criminal from another.
The Unit's attempts to trap a serial killer leaves Mackenzie fighting for her and her best friend's life.
Stone heads undercover to expose a high powered businessman, but experiences a crisis of conscious when he discovers a young prostitute he has cared for is in danger as a result of his actions.
Church becomes convinced he is being stalked by a man who holds him responsible for the murder of his girlfriend, causing him to jeapordise the Unit's current operation: busting an illegal tobacco ring.
When the Unit try to nab a standover man for murder, Angie's relationship with an informant results in a confrontation within the ranks; the Stingers having to face the fury of one of their own.
The unit seems on shaky ground when homicide attempt to charge Church with murder, but are devastated when Stone goes beyond the call of duty to save Church.
Mackenzie is faced with a choice between her personal happiness and her successful career, when she becomes involved with a charismatic art thief, who entices her into believing that love is more important than the law.
Oscar Stone's killer is brought to trial in a situation of high security. The accused is represented by a high profile criminal barrister, Ingrid Burton. That and the presence of a mysterious Mr. Brown in court, has the police on edge.
When Church goes undercover as an armed robber, he is busted by a young cop, who so impresses Harris, that he arranges for her to join Undercover for a trial period. Meanwhile, the brutal murder of an old woman sees Danni go undercover as a carer in a retirement village.
Church's undercover assignment results in the kidnapping of a drug dealer's son. Meanwhile, Chris finds herself on what appears to be a routine surveillance job at a video store. It proves, however, to be anything but routine.
An undercover attempt to sting a drug distributor results in tragedy, with accusations made against an undercover operative.
Harris sends Chris undercover to infiltrate a violent gang of brothers despite Church's reservations about her inexperience. When Church realises that Chris has a longstanding relationship with a street contact who gets her closer to the gang, a window on Chris's former life begins to open.
A middle-aged woman, Helen, brings a cardboard box into police headquarters claiming it contains a bomb. In fact, it contains something even more bizarre, that is determined to belong to her husband, Miles. A series of mishaps prevents Angie from returning the box to Miles, and Ingrid Burton soon complicates matters when she reveals that she will represent Miles in his attempt to sue the police and Angie. Meanwhile, when Harris is forced to submit to a random drug test, another mystery comes to light.
Church's hapless persuit of the coke happy Vidarl crew takes a turn for the worst when most of them turn up dead - victims of a bloody armed robbery. There is, however, one survivor, but there's a catch.
Church goes undercover on a building site to investigate union corruption and the disappearance of activist Craig Shore. Matters are complicated when Ingrid Burton enters the equation. However, things take a surprising turn when Church and Burton discover they have more in common than they thought.
Harris puts Church undercover on the construction site where Ingrid Burton's client, Steer, was murdered. Meanwhile, Church is convinced that Harris is corrupt, and goes to extreme lengths hoping to prove it.
Church and Angie continue piecing together links between Conrad, suspected drug kingpin Stig Endquist and known union basher Rick Tyson. Church suspects Harris of protecting these men. Harris, for his part, suspects Church of corruption, and assigns Chris to spy on him, in an attempt to bring Church down. But the tables are turned when it is revealed that Chris has her own secret - and Church is the only one who knows the truth.
Harris is clearly losing it and is convinced that his officers are out to get him. In his paranoid state, he decides it's time to do something about Church - kill him. Meanwhile, Angie is having a hard time dealing with the intimacy between Church and Ingrid - the lawyer who got Stone's killer off the hook.
The cat is well and truly set among the pigeons when Church and Harris are forced to work together determined to catch two small-time dealers. Things get complicated when Chris, who knows nothing of Harris and Church's dilemma wants to set up a bust of her own.
As Harris' mental state continues to deteriorate, Church and Harris find themselves under extreme pressure to clear their names after drug boss, Stig Endquist, calls the Police Integrity Unit in to investigate the duo's involvement in a drug trade.
When drug boss Stig Endquist survives an attempt on his life, Church convinces him that the assailant was Stone's killer, Conrad. Endquist agrees to put out a bounty on Conrad in retaliation, and when Ingrid gets an inkling of what Church is up to, she threatens to expose him. Soon after, though, she is kidnapped by Conrad. The race is on, as Church faces a battle against the clock to find Conrad and discover Ingrid's whereabouts.
With Ingrid missing for seven days, the intensive police search to find her begins to lose momentum with everyone beginning to believe they're looking for a body.
Angie is undercover in an Art Gallery looking for an insider connection to a spate of robberies when a balaclava clad bandit bursts in. The gallery manager is held at gunpoint while the rest of the staff are forced into the storeroom. After being released, the prized Loxton painting is missing and an investigation ensues. Meanwhile, Harris has a copy of the Church/Ingrid sex tape in which Ingrid professionally compromises herself.
Harris attempts to teach a mate a lesson in crime and punishment, but his plan backfires with disastrous consequences. Meanwhile, news of Church's tape implicating Ingrid Burton has been leaked to the papers.
Angie meets with two brothers, who are looking for a nurse to do a mysterious job. She's amazed when she's quickly hired by the pair and has to accompany them on the job immediately. Without backup, Angie is forced to go with them or miss out entirely on knowing what they're up to.
Chris Dichiera's future is jeopardised when she's forced to shoot dead a former squat mate.
Angie, Harris and Sophie lose a colleague when a siege situation erupts at Police Headquarters.
While investigating the murder of a friend, Church loses Angie's heart to his boss, Luke Harris.
Church and Angie penetrate the liberated world of swinging couples and find that love really is a drug.
Church pushes an unstable informant to take him deeper into the drug trade, unwittingly sparking off a series of murders.
Christina's relationship with a lesbian clubber turns to tragedy when she discovers that her lover is a murderer.
When the undercover unit investigate a renegade young detective working subversively in a suburban station, they discover he has all the qualities to become the new undercover recruit.
New rookie Leo Flynn takes the undercover unit on a wild and merry dance, investigating a drug war between two rival ice cream vendors and ends up biting off more than he can chew.
Harris takes an impulsive trip to Singapore in an attempt to win Angie's heart and protect her from Internal Affairs. This plan backfires when she and her sister are taken hostage by a drug boss.
Angie's latent feelings for Church resurface when a young deaf girl arrives at PHQ declaring she's his daughter. When Harris uses her to solve a crime, all hell breaks lose.
The undercover unit simultaneously pursue a European war criminal and her drug dealing son, thwarting Harris and Angie's attempts to consummate their romance.
A sexual indiscretion of Harris' comes back to bite him on the arse when a demented bunny soldier sets her vengeful sights on Angie.
Church makes a dangerous call when faced with a conflict of loyalty between Harris and his old boss, Bernie Rocca.
Flynn endangers his life and that of his pregnant sister on a deadly assignment with two cop killers.
Chris risks her life and puts her sexuality on the line to sting a sadistic chef for murder.
Church goes undercover in a dodgy furniture removal company suspected of being a front for a drug courier business. But his affair with Ava, the former girlfriend of the owner of the company, gets the seasoned operative into a spot of trouble. Meanwhile, Constable Leo Flynn tries to make amends with Constable Chris Dichiera, whom he let down on a previous case.
Leo goes undercover in order to bust a racehorse stealing, coke dealing porn king. Meanwhile Church has a surprise meeting with prostitute Lauren Davies.
After Flynn is almost killed in a buy bust gone wrong, Church goes undercover as a spiritual medium to hoodwink an international gun runner.
Sophie takes Church to lunch with two of the state's biggest criminals. But will the meal be Church's last?
Harris is blackmailed by an adversary from his past who threatens to reveal his psychiatric disorder. Meanwhile, Angie receives a proposal of marriage.
Angie and Harris' wedding day promises to be the happiest day of their lives. There's just one minor hitch...
With Harris confined to a psychiatric hospital for ECT treatment, his nemesis, Brett Linton, abducts Angie.
Disillusioned with her new husband, Angie leaves him and transfers to Homicide.
Flynn finds himself in a treacherous love triangle when he is seduced by a colleague.
A teenage love affair involving one of the team's children puts the operatives at risk on a major drug job.
Angie faces an enormous decision regarding an aspect of her relationship with Harris and Chris' life is left in the balance when she rekindles an old relationship.
Eight months have passed since we last caught up with the Undercover Unit. Chris has pulled through and almost completed her rehabilitation. She has moved in with Leo, who has helped greatly in getting her back on her feet. She's almost ready to go back to work - until she has a startling revelation of what really happened to her on the night she was shot. Angie gives birth to a healthy baby boy. And Harris makes sure he's present at the birth.
In a race against the clock, Church goes undercover as a hitman in a desperate attempt to save a kidnapped girl.
Church's efforts to nail a high profile people smuggler are thrown into chaos by a rogue Homicide detective - hell bent on playing undercover cop.
After a wild night, Flynn wakes up in bed with a corpse, and has difficulty proving he's not the killer.
Chris becomes emotionally involved with a target who agrees to turn informant in exchange for a date with her.
Church's career is on the line when a federal police officer learns of his contrived relationship with the daughter of an illegal immigrant.
Working undercover with armed robber Damien Broadbent, a masked Leo Flynn is forced to steal the proceeds of an illegal poker game at gunpoint – and the main players happen to be none other than Peter Church and Bryan Gray. Back at PHQ, Flynn comes clean to Church and hands back part of the haul (an expensive engagement ring) on one proviso – the cops can't pressure Broadbent for their booty as it could blow his cover and put his life at risk. Church agrees, but when Anna Trukan finds the ring, she believes Church is offering his hand in marriage. Without the heart to tell her otherwise, and with Broadbent demanding that Flynn gets the ring back, Church is pulled from all sides.
Flynn's old flame guides him deep into the world of body art, heroin and murder.
Angie and Harris face every parent's nightmare when their son Josh falls victim to a child abduction ring.
Harris goes undercover as a translator for a Malaysian drug cartel and descends into a world of opium smoking and prostitution.
Church risks radiation exposure in a desperate attempt to avert the detonation of a dirty bomb.
Three homeless men have been murdered, and Church goes undercover into the homeless community to track down the killer. Without the back-up of weapons or communication, Church submerges himself in this shadow world. But he quickly learns that murder might not be the only thing going on, someone is making what look like snuff movies, featuring the murdered homeless men.
Betrayed by an old love, Church faces execution at the hands of a drug dealer.
Church and Gray fake the death of two people in order to sting an elusive crook known as the Coyote, only to discover they might have targeted the wrong man.
He's killing innocent tourists, now Angie goes face to face with evil ...
Angie pursues a journey of revenge after the shocking murder of her sister.
After meeting up with an old friend, Chris is horrified when he commits suicide and tries to prove the incident was murder.
An investigation of a liquor store robbery takes an unexpected turn when one of the gang members claim they are being protected by ""The Walrus"", a corrupt cop. Harris suspects that the Walrus is the Head of Armed Robbery, Geoff Skinner. When Megan Walsh reveals that Skinner is her old friend and mentor, Harris begins to suspect that she may tip Skinner off, and his suspicions are heightened when Megan starts asking him questions about the case after seducing him. Meanwhile Katherine suffers an extreme bipolar episode and Harris is forced to confront the fact that their relationship is at breaking point. Katherine leaves for a posting in WA, leaving Harris shattered.
When Harris and Masters locate a massive quantity of cocaine in the boot on an imported U.S. Mustang, it looks like they're on the verge of a huge arrest. But things go haywire when the importer of the vehicle, property developer David Cale, refuses to take possession of the vehicle due to a small rust problem. Suddenly Harris and Masters are left holding a whole lot of coke with no-one to bust. Masters soon pulls the pin on the operation leaving Church undercover in the importer's garage without any back up. When the bad guys come calling looking for their cocaine, Church finds himself in a very sticky situation with no way out.
Church has established himself as the muscle in a close-knit Italian crime family, prolific producers of methamphetamines. When the head of the family discovers that his son has been seen in the company of a cop, he takes the cop hostage and orders Church to kill him. Church is horrified to discover that the cop is Harris, and that Harris has been buying opium off the son. Church manages to fake the shooting, but the son soon tracks Harris down. As the Undercovers move in to bust the family, Harris is finally forced to make a choice between his addiction on one hand, and his career and family on the other.
Chris convinces a young prostitute to give her information about a blackmail scam at a brothel. The client she names refuses to talk, and then the prostitute is found with her tongue cut out. Angie goes undercover in the brothel as a cleaner, and is surprised to discover that Reg Masters sees a dominatrix who works there. A mortified Masters agrees to go in wired and use his relationship to set up a cocaine buy with the owner, who is none other than Steve Wylie. Wylie is brought down, which leads Harris to consider the recent events surrounding the death of Wylie's brother, who undercover believed to be a major player in the criminal world. Harris enlists Angie's help to investigate his theory that Megan Walsh is corrupt. Church refuses to consider the possibility, and it soon becomes clear why – he and Megan are lovers. Harris is forced to offer proof of Megan's treachery – she slept with him for information.
While on a deep cover operation, Church is intercepted by a couple of thugs and thrown off a building. Waking in hospital with minor fractures and head trauma, Church discovers his memory has been completely wiped. He can't remember his name, how he came to fall from the roof, or anything of his past. The only clue is his driver's license, which names him as Josh Brisbane. Church soon learns Josh Brisbane is a gun for hire, contracted to take out underworld crime figure Nick Tascone. While his instincts tell him to cut and run, a confrontation with his target becomes inevitable as Tascone moves to finish the job of terminating his would-be assassin.
When Church misbehaves on a drug bust and is accused of corruption by an unnamed informant, he is investigated by Internal Affairs. The Undercover team unearth evidence that an IA cop is framing Church, but Harris orders them to draw a line under the investigation. Instead, he sends Megan to search Church's house, where she finds stolen goods - damning evidence that Church is corrupt. Church admits his corruption to her and in turn she admits her own. Together, they devise a plan to rip off the drug bust cocaine and escape. When Church is arrested for possession of stolen goods he and Megan are forced to bring the coke deal forward. It is only when Harris arrives at the scene of the deal that Megan realises it's a sting, and that Church is wearing a wire. She stares at Church in disbelief as she is arrested and taken away.
The city erupts into violence as underworld gang members start knocking each other off - but with Flynn and Church undercover in the rival gangs, how long before one of them becomes a target?
Angie goes undercover as the long lost daughter of contract killer William Franks. A notorious assassin, Franks hasn't seen his daughter since she was a three year old and he was imprisoned for the murder of his wife. Though Angie initially has no qualms about such a deception, as she comes to know Franks she comes to believe that he's not the monster she first thought. When evidence comes to light suggesting Undercover has been wrongly targeting Franks for an intended hit on anti-Islamic pop philosopher, it appears that Angie's suspicions of Franks' innocence may be true. It's only at the eleventh hour, in a hostage situation, that Angie discovers Franks' true, heartfelt purpose.
The murder of an illegal immigrant leads to an undercover brothel trading in sex slaves and a missing girl suffering from Stockholm syndrome.
When Chris is involved in a car accident after a night on the town she is horrified to discover a nine year-old boy was seriously injured. Chris questions her own culpability given that she hadn't slept and her reaction times were down. Her problems escalate when the boy's mother claims Chris was in the wrong and she intends to sue. Chris doggedly pursues every lead to prove her innocence, and in the process discovers evidence that the boy's doctor may be faking medical records in order to fraudulently claim accident compensation. When Harris shuts down the investigation Sophie takes matters into her own hands and goes undercover as a patient. Fortunately her audacious move pays off and the doctor is brought to justice. Meanwhile, Harris starts to feel threatened as Angie and Sean Hunter take their relationship to the next level.
Harris' obsession with Angie's new partner spirals out of control when one of the Undercover unit falls victim to the serial killer.
Angie frantically tries to clear her lover's name while Harris works equally hard to convict him as the serial killer. Convinced Sean Hunter is innocent of the attack on Sophie, Angie sets out to exonerate the man she loves and catch the real serial killer. She suspects Richard Kline, who blames Hunter for the suicide of his wife, a former patient of Hunter's. Chris goes undercover on Kline, which leads to the discovery of trophies from the previous killings on Kline's premises. Hunter is freed and an already off-centre Harris, realising he has lost the battle, slips into bipolar meltdown and is forcefully taken into emergency psychiatric care. As the current is administered to his temples we go out on Angie and Hunter happily making their wedding plans. As they tenderly embrace, the cold disregard on Hunter's face tells us that Angie has become victim of a very lethal deception.
