Jill St John was the original female lead but walked when her salary hadn't been deposited in her account.
Richard Roundtree says no words in this film
Glenn Ford was paid $100,000 for just 2 days work.
In the first beach scene, one of the speedboat thugs is wearing a "Black Whale III" T-Shirt. This shirt was worn by Miguel Ángel Fuentes in the movie The Bermuda Triangle (1978) as it was the name of the boat in the movie.