Ventress' sanity is called into question when he reports of a UFO sighting on the moors during a thunderstorm, leaving Nick with the task of fighting for the veteran's future in the force and to play peacemaker between two feuding neighbour's. Meanwhile, Greengrass is delighted to win a holiday cruise, until a trip to Whitby reveals he suffers from sea-sickness. However, he quickly spots a way to make money by selling the tickets to a businessman planning to his escape with his mistress, whilst Eileen learns a valuable lesson when her charity collection is stolen.

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.