ट्रिविया

Although by this point Sidney Poitier had been making films for 15 years, this was the first film he made in which his race was neither mentioned nor relevant.

Interior scenes were filmed aboard a British Type 15 frigate, the H.M.S. Troubridge. This is why even though this is supposed to be an American frigate, much British military equipment can seen around the ship.

The U.S. Department of Defense withheld full cooperation in making the picture after negative portrayals of the U.S. military in Dr. Strangelove or: How I Learned to Stop Worrying and Love the Bomb (1964) and Seven Days in May (1964). These pictures strained the Pentagon's relations with Hollywood filmmakers. However, according to a contemporary article in the Los Angeles Times, director James B. Harris and screenwriter James Poe were able to visit a U.S. Navy destroyer based at Norfolk, Virginia for pre-production research in late 1963.

The tape recorder Munceford uses is a 1964 Philips EL3300 - the world's first commercial compact cassette recorder.

This is the first film shot at Malta Film Studios, which was called Mediterranean Film Studios at the time. The studio was built in 1964, with a water tank built specifically for this film. Another water tank would later be built in 1979 for the film Raise the Titanic (1980).