After spending the night in a hotel with her married lover, Peter Harris, Inspector Gina Gold gets a shock when his wife, Mary, turns up at Sun Hill: Peter has disappeared and she has been sent his wedding ring with a note saying. 'How much is your husband worth?' When Gina confesses to DI Neil Manson why she can't interview Mary, he agrees to keep schtum about her affair. But when DI Sam Nixon finds a blackmail note and surveillance photos of Gina and Peter in Peter's office, she annoyed with Neil for keeping quiet. DC Mickey Webb realises that Peter's been kidnapped by his neighbour, Barry. Gina and Mary break into Barry's house, immediately smell petrol and are horrified to discover Peter tied up and Barry standing over him with a lit match. Mary clings to Gina for comfort - not realising she is the 'other' woman... Elsewhere, Pc Lewis Hardy comes unstuck when he allows his girlfriend's younger brother to become a drugs runner.
