Gordon (Chard Hayward) works as a handyman at the Rocky Beach Motel. He proceeds to spy on singer and actress Marie Coleby (Deborah Coulls), who is bad tempered, bossy and constantly barks orders at and berates him all day. Later that day, when she packs up to drive to the airport to pick up her sister, Jenny (Louise Howitt), he intrudes on, and rapes her. When she bites and calls him an animal, he drowns her in her fish tank in a fit of rage. While trying to hide her body in a garbage bag, her neighbor Billy Sheperd (Les Foxcroft) catches him in the act and is also killed by Gordon, who also poisons Billy's dog. Later, Jenny is driven home from the airport and finds the house empty. She later finds her jewels of her necklace in the fish tank and even finds Billy's dog floating in the water at the beach. She tries to tell Billy but sees his body lying on the couch and mistakes him for merely napping. She tries making a few phone calls to find her sister and even tries calling Billy later, but receives no answer. She then meets Gordon, whom she draws suspicion towards due to his knowledge of the house, which are later confirmed by sundown when she finds a muddy footprint on the carpet that was attempted to be cleaned off. She runs back to Billy's house to get help from him only to find his body hidden in his garden shed. She runs back to the motel to call the police only to find Gordon there waiting for her, dressed in a suit with presents for her. He cuts the phone wire while she calls the coastal guard service. He then proceeds to taunt her and also tries to break into the house to no avail. Two policemen arrive shortly, officer Clyde Collings (Roger Ward) and patrolman Rex "Pops" Dunbar (James Elliott), but Pops is killed by Mason with a shotgun from the cop car when Pops tries to radio for backup. Collings reveals to Jenny that Gordon has a history of raping other women who never laid charges on him because of their "irate husbands". He then tells her to make a run for the highway since he won't see her in the dark, but she stops when she finds Marie's body in the backyard and mourns over her. Collings tries to strike a deal with Gordon, who refuses, but Collings vows to kill him after he sets his partner (who survived the gunshot) on fire. Collings chases and fights him in the swimming pool and eventually drowns him. Jenny, who eventually ran out and hid in the bushes on the highway, comes out of hiding when Collings' car drives by and orders her to come out. It's revealed that Gordon survived his drowning and killed Collings. He proceeds to strangle her, but envisions Marie in her place and has a mental breakdown. Gordon is then hit by a passing motorcyclist and is thrown into Collings' car. Another cop car drives by and the two officers inside find Jenny lying on the road. One of them inspects Collings' car and finds a barely conscious Gordon inside about to shoot him with the shotgun, but that officer shoots and kills him.