Dodgy car dealer Arthur Daley (George Cole) specialises in moving shonky merchandise to unsuspecting punters. To protect him from customers with a grievance, and the long arm of the law, Arthur hires jailbird Terry McCann (Dennis Waterman) as his 'minder'. McCann, an ex-boxer, has decided to go straight, but with "Arfur's" shady deals, Terry has his work cut out for him. When Terry leaves, Arthur's nephew, Ray, steps in to be his minder, but is initially a little wet behind-the-ears.