The Colors of Iris (1974)

Original title: Τα χρώματα της ίριδος

A mysterious disappearance takes place during the shooting of a commercial on the beach in the early morning hours. An unknown man suddenly comes into the shot, then walks into the sea holding an umbrella and seizes to exist, before the bewildered eyes of the whole crew. After the police are notified, a confusing array of red tape manoeuvers begins, revealing the close affiliations of the Authorities with the advertising company manager and the whole mechanism of Mass Media, all of which are trying not to investigate the event but to conceal or even exploit it in their own interest. Only the musician involved in that commercial is trying to figure out what really happened.