Nick agrees to work on loan with CID and is paired with his old flame Jill to bring down a local gangster who has recently opened a new nightclub in Whitby. The pair go undercover as a couple at the club, but things take a dangerous turn when their cover is blown and Jill is kidnapped. Meanwhile, Greengrass befriends Billy Black and the pair plan to make a fortune at the Ripton races, whilst baby Katie is christened.