Shortly after filming was completed in 1950, the submarine H.M.S. Truculent went down in the River Thames with a heavy loss of life. The incident is referenced in the opening credits, and nearly caused this movie to be withdrawn from distribution.
Armstrong's quote, "And all I ask is a tall ship/ And a star to steer her by" is from the poem, "Sea-Fever", by John Masefield.
The opening prologue states: "This film was completed before the tragic loss of H.M.S. Truculent, and earnest consideration has been given as to the desirability of presenting it so soon after this grievous disaster. The producers have decided to offer the film in the spirit in which it was made, as a tribute to the officers and men of H.M. Submarines, and to the Royal Navy of which they form a part."
This movie features Wylie Watson (Able Seaman Nobby Clarke), who played Memory in The 39 Steps (1935). Also, James Hayter (Able Seaman Higgins), who played Mr. Memory in The 39 Steps (1959).
Michael Caine, aged 17 at the time, worked for Producer Jay Lewis at the time and worked on this film as a tea boy.