From mission blue:
Falco first met Cousteau when he was 25 years old. He joined Cousteau and his team as a volunteer exploring a shipwreck off the coast of Marseille. He soon became chief diver of the team, and then captain of the R/V Calypso.
In 1959, he lived for 7 days at a depth of 10 meters in the first house under the sea in the Mediterranean, becoming one of the world’s first Oceanauts.
The movie which captured Falco’s time as an Oceanaut is World Without Sun.