The Bill (1984) : 7x13

Dashwood and Roach investigate a burglary at a scrapyard. Dashwood recognises the name of an ex-copper who knows Roach and Dashwood thinks Roach is prejudiced and too helpful. The ex-copper turned security guard's wife comes up with a possible suspect. Cathy investigates poison pen letters sent by the recipient's husband. Bob says the police can't do anything about them. the husband comes to the station and asks for protection.