In quiet, sleepy summer Oslo, a murder occurs—bold and defiant. The culprit left the police not only the instrument of the crime, but also a small diamond shaped like a five-point star, hidden under the eyelid of the deceased. Soon the Norwegian capital is shaken by a chain of mysterious events mystically linked to the number five: they are persistently reminded by the five rays of the star and a mutilated hand. Every fifth day the police find a new victim of the mysterious criminal, who each time manages to slip away unnoticed.