Never Let Go (1960)

John Cummings, an unsuccessful cosmetics salesman, has his unpaid-for car stolen by one of the hoods in the employ of Lionel Meadows, the sadistic organizer of a London car conversion racket. The car was not insured, and since the police appear indifferent to his plight, Cummings decides to find it himself -- and gets himself involved in an underworld battle.