Christmas Street's new CID chief, Jack Carter, immediately upsets Chief Inspector Barnard by arresting local dignitaries. Pcs Jitlada and Green become involved with a homeless young couple who are being chased by an armed bounty hunter.

A one-man crime wave hits Christmas Street in the form of an impostor and DI Jack Carter and DS Janet Miller investigate local drugs dealers – one of whom turns out to be the son of Chief Inspector Barnard's new love.

After a bungled drugs bust, DI Carter is left to salvage something from the few scraps he has. Carter and the team were after ambitious small-time dealer Gerald Ridley but chances of them getting him now look slight. Later, Pcs Green and Lawtry go to help social services take two children into care. However, it turns out they're ill-prepared and unequipped to deal with the mother and find themselves in the middle of a hostage situation.

Pc Clive goes in for some heroics involving one of Mulholland's tenants, and DI Carter goes after the gangster. But will Mulholland fall?

Andy offers to work off his debt to dodgy landlord Mulholland – but ends up having to set fire to a house.

Carter's confidence is shaken to its core when he pushes his luck too far.

Miller finds herself having to go beyond the bounds of duty when she tries to stop two brothers dealing in stolen videos. A girl tries to have her dad arrested to end his life of crime – but her plan has tragic consequences.

Alfie Stokes is a sadistic, underworld-type who now claims to have found God, and he's DI Carter's star witness in the prosecution of Barry Roberts, a local drug dealer. But then former sergeant Yvonne Mackey turns up with some difficult question…

Back at Christmas Street, Nick is livid that Sgt Dobson forgot to enter him for his sergeant's exams and threatens to take action.

Two young burglars break into DI Carter's house and steal his illegally held replica Colt 45 pistol, leaving everyone involved in hot water. Meanwhile, Colin is drawn into a couple's kinky fantasies while on a surveillance operation.

Pc Pete Redfern is having a rough couple of days. Nobody attends his police Q & A session on the Carcroft Estate, he's splattered with ‘water' bombs and then he's suspended for clipping a ‘lippy' boy around the ear. Then local lad Euan (one of the bombers) goes missing, but the Christmas Street cops don't get involved until late in the day – perhaps too late. Suspended Pc Pete Redfern's knowledge is sorely missed when the police try to find him.

DI Carter is put in a safe house after an arch enemy, Mark Dixon, is released from a psychiatric unit intent on revenge, convinced that Carter set him up. Dixon, a vicious rapist and murderer Carter put away some years ago, has already killed Carter's old sergeant. Meanwhile, Pcs Green and Law are assigned an undercover operation to find a local bootlegger.