The Metropolitan Police Serious Crimes Squad sweep into Sun Hill and commandeer the station's briefing room, setting a few noses out of joint in the process. They are there to investigate the murder of a police informant, who at the time of his death was under the protection of Sun Hill CID. DI Burnside and DS Roach come to blows when Roach refuses to share the blame for withdrawing officers from the safe house, and accuses Burnside of corruption.

Sun Hill is in shock after the death of WDS Jo Morgan, none more so than WPC Ackland who is still racked with guilt over her death, and PC Loxton who is forced to apologise to a pair of loudmouthed youths after he threatens them.