The Big Blue - Luc Besson (1988)

Enzo and Jacques have known each other for a long time. Their friendship started in their childhood days in the Mediterranean. They were not real friends in these days, but there was something they both loved and used to do the whole day long: diving. One day Jacques' father, who was a diver too, died in the Mediterranean sea. After that incident Enzo and Jacques lost contact. After several years, Enzo and Jacques had grown up, Johanna, a young clerk in an insurance office, has to go to Peru. There she meets Jacques who is being studied by a group of scientists. He dives for some minutes into ice-cold water and the scientists monitor his physical state that is more like a dolphin than human. Johanna can not believe what she sees and gets very interested in Jacques but she's unable to get acquainted with him. Some weeks later back in her office, she finds out that Jacques will be competing in a diving championship that takes place in Taormina, Sicily. In order to see Jacques again she makes up a story so the firm sends her to Italy for business purposes. In Taormina there is also Enzo, the reigning diving world champion. He knows that only Jacques can challenge and probably beat him. This time Johanna and Jacques get closer, but Jacques, being more a dolphin than man, cannot really commit and his rivalry with Enzo pushes both men into dangerous territory...