A young Russian girl leads Dale Smith out of a nightclub, where he is promptly attacked by three men. Despite Smith's protests, Supt. Chandler assigns DI Cullen to investigate the assault. They track down the Russian woman, Natasha Ivanova, through a language school which seems to be recruiting students to work as prostitutes. Natasha is desperate as her visa is about to expire, and her sister has disappeared. Her sister is found murdered, and Smith realises the men responsible for her death and his assault are linked to a man from his old army unit (episode: Blurred Around the Edges).

Hoping it will convince Supt. Chandler to endorse his transfer to SO19, PC Smith volunteers with PC Klein to 'babysit' Clive Allein, the victim of a gay bashing who is reluctantly testifying against his assailant, Gary Cook, in court the next day. Smith nearly blows it when his angry reaction to Clive's partner Ian Jones's teasing causes Jones to run off, where he is promptly attacked, and Allein refusing to testify, until Smith convinces him otherwise. The trial goes ahead, and the attacker is found guilty, but further threats from Cook's friend Paul Taylor cause Ian to storm off again, this time he goes missing. Smith and Klein fear the worst when a stabbing victim is reported, but it turns out to be Paul Taylor who is the vicitm, and Ian Jones the attacker.

PC Smith and PC Klein attend to Mr Kennedy, whose house and garden shed have been attacked by vandals repeatedly over the past few weeks. When Kennedy threatens to take matters into his own hands, Smith casually comments that he wouldn't blame him if he did. Smith and Klein both apply for new jobs - Smith submits his application to SO19 and Supt. Chandler wants Klein to take the position of partnership officer at the Town Hall. When Kennedy shoots a young boy, and insists that PC Smith told him to do so, Klein reluctantly confirms what was said, and Smith accuses him of grassing him up. After attacking Klein in the corridor, and under investigation by CIB, Smith is suspended from duty.

PC Klein is offered the position of partnership officer, but he is shunned by the relief, who think he grassed Smithy up to get the job. Sgt. Cryer has a funny feeling about Frank Kennedy, and decides to do some digging of his own, and he encourages Smith to do the same. With Klein's help, Smith infiltrates the gang of youths intimidating the local residents, and discovers that the real estate firm Mather & Devine is indeed behind the harassment. Meanwhile, Cryer uncovers the fact that Kennedy was a notorious East End gangster named Ken Franklin who stored weapons for the Kray brothers, and that Kennedy's claim of shooting in self-defence is disproven by the forensic evidence and a statement from the other gang member. Smith is re-instated, Supt. Chandler approves his transfer to SO19, and Klein turns down the partnership officer job.

PC Nick Klein is back in the safe house, but when DS Phil Hunter gives the address to Dennis Weaver, a hitman is contracted to kill Klein. Meeting with the hitman to retrieve the gun and a photo of Nick's body, Weaver realises Hunter has set him up when the police lead by Supt Okaro and DCI Meadows swoop in on them. Escaping into North Canley Forest, a terrified Hunter barely escapes with his life as a maniacal Weaver swears revenge for his treachery. With Weaver on the loose, however, Nick Klein is relieved of duty and placed in deep witness protection far outside of London, but not before Hunter and Sgt Dale Smith have a chance to clear up their differences with him. Police Staff Polly Page investigates a forged drivers licence, but is reprimanded for exceeding her remit as a civillian staff member. Polly visits Cathy Bradford in a secure psychiatric unit, where Cathy tells her she is ""undercover"" in the hospital. Considering recent events and Bradford's taunts, Polly resigns from Su