Josh, Alex, Campbell and Gretel discover the secret lair of the Silver Shadow: a long-forgotten superhero from the 1950's. Meanwhile, the Silver Shadow's arch enemy, the Crab, has started training his granddaughter, Fiona, to take over the family business.
When the Silver Shadow sends his team on their first mission - to bust a bicycle theft ring - they find that fighting even petty crime can be harder than it sounds.
Alex is seen with Josh after school, and to prevent suspicion invents a story that they are going out - much to Josh's dismay! Meanwhile, Fiona goes on a recruiting drive for evil henchmen, and tries to steal an ancient helmet.
A series of public transport robberies leads the Silver Shadow team to a confrontation with Crab Girl. But, with the team more focused on competing with each other than fighting crime, their superhero careers may come to an untimely end.
Campbell borrows the Silver Shadow's exoskeleton as protection from the school bully at camp. When a thief steals the high-powered suit and embarks on a crime rampage, Campbell has a lot of explaining to do.
The Crab believes the Silver Shadow is a student at Bateswood High School, and Fiona enrolls at the school there to lure him out. But is even achieving world domination worth the pain of posing as Alex's friend and organizing the school dance?
Gretel lets her big secret slip to her best friend, Stephanie, who promptly blackmails her way into joining the team. Stephanie soon learns that there is more to being a superhero than a costume and mask.
Gretel responds to an intruder alert, deep in the Lair's tunnel network. She not only discovers the culprit (a rat), but also the previously unknown Tunnel 54 and its disturbing secret - a live nuclear missile.
Josh lets his duties slip when he decides to track down one of the Silver Shadow's teenage sidekicks from the 1950's. But his distraction may prove costly when Crab Girl kidnaps Alex.
When Crab Girl gets her hands on the Silver Shadow's journal, the hands of time are turned back to a superhero's convention in the 1950's. Crab Girl and Josh both learn some unsettling details about their mentor's origins.
It's a fine line between truth and fantasy when the Crab and Fiona convince Alex that the Silver Shadow is a figment of her imagination in the hope that she will lead them straight to the Shadow Lair.
Tensions are running high in the Shadow Lair, as it becomes clear that the Crab knows the team's identities - and may already be closing in on their headquarters.
The Silver Shadow team must work together to stop the Crab's master plan to become immortal. When Fiona realizes her role in the Crab's grisly plan, even she is prepared to help them.