In 1850 the Earl of Taplow and his family return from Italy to Taplows, their country house, with their retinue of servants, led by butler Jarvis and house-keeper Flora. George Cosmo, a confident youngster, arrives seeking employment as the second foot-man, bringing with him forged references. Whilst Flora is willing to take him at face value, Jarvis is less certain. However the sudden departure of under-butler Frank creates a vacancy which needs filling immediately. George is taken on. First footman William is not impressed but he catches the eye of Grace, nursemaid to the earl's handicapped young son Harry.
A grand dinner is to be held and George gets William involved in a scam whereby they will obtain cheap fish for the occasion. Unfortunately the fish is bad and the guests go down with food poisoning. Andrew, the sneaky, bullying under-butler, is aware of what has happened and wants money to keep quiet. Grace comes to George's aid by selling her engagement ring to raise the cash.
William trips on a loose rug and drops young Harry, who eventually dies. Accusations fly amongst the servants as to who is to blame but the Earl concedes that it was an accident. However a planned banquet is cancelled, allowing the staff to enjoy the chef's sumptuous fare. Grace takes the death to heart and picks flowers from the Earl's orangery to provide a blanket for the little boy. The Earl sees this as vandalism but blames and sacks Esther, a maid who had been tormenting Grace.
Flora confronts Jarvis after discovering he has been embezzling wages for years. Faced with exposing him, she must decide where her loyalties lie - above or below stairs. Elsewhere, Fred has to compete in a race to keep his job, while Grace and George agree to keep their blossoming relationship secret.
New Year's Eve offers a chance for celebration for the staff, but the merriment does not extend to William, as his nightmares over Lord Harry's death continue to torment him, leaving him vulnerable to under-butler Andrew Adams' goading and cruelty, which leads to a terrifying and violent showdown.
Young lovers George and Grace are almost discovered alone in the middle of the night, prompting Flora to demand a moral clampdown, against Mr Jarvis's better judgement. As the hunt to unmask the errant pair rages, the butler decides to move the household to Cumbria for a few months, leaving Flora heartbroken as she realises her true feelings for him.
