Plot synopsis: During a journey of the "Ceder", the Captain, von Moltmann, disappears. It looks like an accident, but it could also have been murder. Attorney Dr. Burger and superintendent Störensen discover quickly that two of the crewmen hated the Captain: Chief officer Rohlfs suspects an affair between his fianceé Gerda and von Moltmann. Chief engineer Sparkuhl thinks the Captain has seduced his niece, who later committed suicide. The court decides that the Captain has gone overboard without anyone else's "help", but the rumors don't come to an end.