A passerby's dog finds the beached-up corpse of lifeguard Leon Richter, drowned with a non-fatal head wound, who was supposed to fill in for colleague-mate Malte Röper, a student with whom friendship since childhood was stresses. Leon's informally in-living, high-pregnant fiancee Finja Werkamp, daughter of region's largest camping owner Jochen Werkamp, acts shocked, her father admits he found Leon a dubious choice, being a poor worker and incurable womanizer. Even Leon's buddy Malte considers him poor father material, and made a photograph, found on Leon's cellphone, of a recent flirt with Malte's girlfriend Paula Liedke. The team must work out what all of them, including Finja, knew when and took how badly.