Sgt. Bob Cryer is approaching his 30th year of service, but some of the senior officers at the station doubt he is still up to the job. Supt. Chandler assigns Cryer the difficult task of resolving a situation where a group of prostitutes are at loggerheads with a local residents group led by Counciller Angela Morris. Cryer suggests a 'zone of tolerance', a non-residential area where the prostitutes can work without upsetting the locals, and manages to convince the girls to give it a try. As Chandler heads off to a charity dinner, a call comes through that the Morris' house has been torched. Meanwhile, PC Smith attends his interview for transfer to SO19 - he is successful, and leaves Sun Hill to join the Armed Response Unit.

When the victim in yesterday's domestic disturbance turns up badly beaten and left for dead, her husband is adamant he had nothing to do with it. Mandy tells Cryer that the woman who was bashed, Cath Evans, was working as a prostitute, and that the Councillor's husband Justin was one of her clients. But Justin in turn, having admitted his deeds to his wife, says that he was seeing Mandy as well, and that on the night of the fire, she turned up late and had blood on her clothes. Meanwhile, Smith arrives at SO19 to find his new friend Julie also made the grade, but on their training course, treats her as the token female. When she beats him on the rifle range it causes friction, and their boss cautions that they have to learn to work as a team.

A gang of masked girls armed with baseball bats run riot at a wedding, but escape with the presents before PC Taviner and PC Hollis can catch them. The gang have been causing headaches for Sun Hill for weeks, and although she is not involved in the case, Supt. Chandler sends DC Kate Spears to visit the local schools, ostensibly to encourage students to join the Met's Volunteer Cadet Corps, but secretly to obtain information on the gang and its members. The gang's violence intensifies and the bride's sister, Debbie Pike, is found badly beaten after an altercation with a mother and her baby on the high street. As rumours about her and Supt. Chandler fly around the station, Kate Spears pushes an eager schoolboy informant too far, and he too is found bashed. When he regains consciousness, he tells Spears that Debbie is a gang member. Debbie admits she arranged for the gang to attack the wedding as she was in love with the groom, and Spears finds herself in grave danger when she confronts t

At her local gym PC Cathy Bradford is concerned that Marti Hunt is being worked too hard by her father Barry Hunt who is also the owner. As she leaves, Bradford agrees to keep an eye out for a petty thief who has been targeting the gym. Back at the station PC Dave Quinnan mentions to PC Tony Stamp that he is thinking of asking out Liz Terry from the Day Centre. Stamp is sceptical and encourages a wary Polly Page to check Liz's history on the police computer. Page is left with a dilemma when the results reveal that Liz used to be a prostitute. Meanwhile a reluctant PC Jim Carver has joined Bradford's gym. He is immediately suspicious that bodybuilder Jay Cutler could be the thief especially when he later sees Cutler selling steroids in the changing room. However, closer inspection of another gym member Andy Little leads to the case taking an unexpected twist.