Spare a Copper is a 1940 British, blackandwhite, musical comedy war film, directed by John Paddy Carstairs and starring George Formby, Dorothy Hyson and Bernard Lee. It was produced by Associated Talking Pictures. It is also known as Call a Cop. The film features the songs, Im The Ukulele Man, On The Beat, I Wish I Was Back On The Farm and Im Shy. Beryl Reid makes her film debut in an uncredited role, while Ronald Shiner appears similarly uncredited, in the role of the Piano Mover and Tuner.
Formby plays a bumbling War Reservist police officer called George Carter who aspires to become a member of the flying squad. The film is set in Merseyside where the battleship HMS Hercules is being built. A group of saboteurs are planning to destroy HMS Hercules by blowing it up. George manages to foil the saboteurs attempts to destroy HMS Hercules, saving the battleship from being blown up by saboteurs. One of the saboteurs, called Jake, is played by Bernard Lee.
Source: Wikipedia