On 20 December 1968, in Lake Helena, a couple of teenagers are brutally murdered by a killer while dating nearby the lake. The young Sergeant Matt Parish is assigned and becomes obsessed with the case, neglecting his wife Laura and son Johnny. On 04 July 1969, another couple is shot on the golf course of Vallejo, and the killer sends letters to three newspapers with a riddle and promising more murders. He kills again, and the police force is not able to arrest him. On 24 April 1978, he writes to a newspaper saying that he is waiting for a good movie about him.
—Claudio Carvalho, Rio de Janeiro, Brazil