Donald MacKenzie, the author of the original novel, specialized in works of fiction centering on criminal activity, rather than detective work. He had been a criminal in real-life and had served time in prison. Writer and Director Seth Holt described him as "one of the prison intelligentsia".
Originally cut to one hour and twenty-nine minutes and was the second feature on a double-bill with Torpedo Run (1958). For a DVD release in 2013, it was restored to a running time of one hour and forty minutes.
This was the last-but-one movie to come from Ealing Studios. Writer and Director Seth Holt said that he wanted it to be "the most un-Ealing film ever made."