The Dark takes place over a period of 36 hours, on the first day of summer. Taxi driver Frane lives together with his sister and her husband in an unusual strange domestic arrangement. Frane learns that his sister is pregnant and he is not sure how he feels about the baby that she is expecting. After his night shift Frane kills a young unknown woman while he is having sex with her. He tries to cover up all traces of the crime, but in doing so he commits two further murders, one of which goes wrong. Throughout the film, the victims tell their stories at the places where the murders took place. On the morning of the summer solstice Frane thinks he has managed to get away with his crimes and he goes with his sister and her husband for a picnic in the forest by the river, not knowing what awaits him there.