If the rent for a safe deposit box at Helvetia-Bank Zurich has not been paid for a while and the owner cannot be identified in the usual way, the safe deposit box may be opened under the eyes of bank director Dr. Peter Jenny, Authorized Representative Norbert Kumeron and Secretary Regula Eggli. At this point the work of researcher Yves Klein begins, who tries to determine the owners or heirs based on the often surprising contents of the lockers. To do this, he travels around the world, experiences dicey situations and takes an interest in personal fates. The work that involves corruption, espionage and people smuggling, among other things, is not always easy for him. And so he would rather set the police on the neck of one or the other of his "clients".