In the beginning of the movie, whilst Gail (Jacqueline Bisset) is diving, she reaches under a part of the shipwreck and gets her arm yanked by the giant green moray eel, which causes her to scream in pain. In real life, her stunt double, Jackie Kilbride, dislocated her shoulder doing this scene. A diver was told to pull the stick attached to her wrist from inside the wreck. When the stick appeared, he pulled with all of his might (as instructed). The scene was done in one take, with multiple cameras, as there was no chance (or need) for repeating it.
An American network broadcast version contained fifty-three minutes of extra footage that was not shown in the theatrical release. This version was broadcast over two nights, and has never been released on DVD.
Louis Gossett Jr., Jacqueline Bisset, Nick Nolte, Robert Shaw, and director Peter Yates had to learn how to scuba dive for this movie.
The picture was notable for its opening underwater diving sequence featuring Jacqueline Bisset in a black bikini bottom and see-through wet t-shirt, thus launching her as a Hollywood sex symbol, and contributing big word-of-mouth for the movie, assisting with its box-office success. According to the book "Hit and Run: How Jon Peters and Peter Guber Took Sony for a Ride in Hollywood" (1996), Producer Peter Guber allegedly once said, "That t-shirt made me a rich man!"
The production shoot ran for 153 days, conducted 8,895 dives, spending 10,870 person hours underwater, and consumed 1,054,000 cubic feet of compressed air.
Peter Benchley: Uncredited, the author of the film's source novel as the First Mate of the "Goliath". The appearance was the second of three cameos in films of his novels, the others being in Jaws (1975) and Creature (1998).