The Silent Enemy is a black and white 1958 British action film directed by William Fairchild and starring Laurence Harvey, Dawn Addams, Michael Craig and John Clements. Based on Marshall Pugh's 1956 book Commander Crabb, the film follows the publicity created by Lionel Crabb's mysterious disappearance and likely death during a Cold War incident 2 years earlier (April 1956).The film depicts events in Gibraltar harbour during the World War II Italian frogman and manned torpedo attacks, although the film's depiction of the events is highly fictionalised. It was the first Universal Pictures film in SuperScope.

Enlisted men refer to Crabb as "Crabbie" throughout, alluding to his crabby nature.