Sunday morning on the lake. On board the yacht “Scheherazade” are Peter Rehstahl, dealer in raw materials, and a juvenile beauty. Unexpected visitors arrive. Son Michael turns up with two guests: Rehstahl’s right-hand man, Frank, and his lover, Valerie. They celebrate the 19th birthday of the “princess”, as host Rehstahl lovingly calls her. The space on board is limited. The sun is beating down. The afternoon passes with drinks and small talk. As the sun goes down, all the family’s secrets are revealed, the quarrel between father and son escalates.