The most financially successful French film of the 1980s.
Although the story is fiction, it is inspired by the lives of divers Jacques Mayol and Enzo Maiorca.
This film was such a hit in France that it played for over a year in theatres.
Luc Besson was very uncertain about which actor to cast in the main role. He proposed the role to Christopher Lambert (with whom he worked in his previous movie), had a meeting with Mickey Rourke and even was suggested that he himself should take the role, since he had such affinity with the character. It was not only until weeks before filming that someone suggested the name of Jean-Marc Barr.
The underwater shots with the dolphins were filmed in the Virgin Islands in large enclosures, and the dolphins were flown there from the Dolphin Research Center in the Florida Keys. The dolphin who appears most often on screen is a male named Natua, who had also taken part in dolphin language experiments because of his intelligence.