Director Gordon Parry supposedly shot two endings for the film, in case his original choice wasn't allowed (it was).
Reportedly, the British censors demanded the excising of all direct references to the gallows, the condemned cell and the final death march.
Promoted as the first time in British screen history that realistic filming of life inside a prison had been allowed.
Victor Fairley worked 12 days
Owen Holder was a front runner for Smith (Harry Fowler)