Blood Beach (1980)
Something or someone is attacking people one by one on the beach. Some of them are mutilated, but most of them are sucked into the sand, disappearing without a trace. What is the creature responsible? Where does it live, and where did it come from? And is there any chance of it reproducing? Meanwhile, David Huffman and Mariana Hill are once-almost-married old friends, reunited over the death of her mother on the beach, and searching for clues in the abandoned buildings where they used to play when they were young.
- Harry Caulder, a harbor patrolman, leaves his Venice beachfront home and greets his neighbor, Ruth, and her dog, Piper, as he heads across the sand to swim to work. As Harry swims off, Ruth is suddenly sucked into the sand by a unseen force. Harry tells police officers Royko and Piantadosi that he heard Ruth scream, but could not find her, and she would not leave without her dog. Harry knows her well because years ago he almost married Ruth's daughter, and he plans to keep searching.
At the Harbor Patrol office, Harry works with fellow officer Hoagy when Ruth's daughter, Catherine, arrives from San Francisco, California. She will stay at her mother's home while the search continues, but Harry warns her that Ruth might be dead. Later, Catherine takes Piper for a walk on the beach and is accosted by Mrs. Selden, a homeless woman, who thinks that Ruth was raped, murdered and buried. From underneath nearby deserted piers, something watches as Piper starts digging in the sand where Ruth disappeared.
That night Harry has dinner with his girlfriend, a flight attendant who is leaving for Paris, France. Meanwhile, Piper escapes from Ruth's home, runs to the beach, and barks as a hole appears in the sand. However, when Catherine comes outside, the barking stops; as she reaches the dog, Piper's head is missing. At the morgue, Dr. Dimitrios reports to Harry, Catherine, Royko and Piantadosi that there was no human skin or hair left behind as evidence on Piper's body.
The next day, it is crowded at the beach and a teenage girl, who is being covered with sand by her friends, screams that something is biting her feet. They pull her out of the sand and discover her legs covered in blood.
At police headquarters, Captain Pearson tells his officers that they are under pressure from everyone, including the Mayor and the city council, and the police organize crews to dig all night on the beach for clues.
The next day, reporter Todd Bell interviews teenagers on the beach. They are not worried since police searched the beach all night, and, in fact, the teens are excited about being on "Blood Beach."
That night at the Harbor Patrol office, Hoagy's girlfriend, Jo, kisses him goodbye and rides her bicycle by the deserted piers on the beach. A rapist attacks Jo, and she fights him until something in the sand beneath him rips out the rapist's midsection.
The next day, Dimitrios theorizes that a creature, perhaps from the ocean, is adapting to a new, subterranean environment.
In the Harbor Patrol office, Harry's girlfriend calls to confirm she will be back that night and he offers to make dinner for her. As Harry hangs up, Catherine arrives and asks him to dinner. He admits he already has plans so they make a dinner date for the following evening. As Catherine leaves, Hoagy realizes that Harry never got over his romance with her. That night, when Harry's girlfriend arrives, her hat is blown onto the beach. She runs to retrieve it, and is sucked into the sand. Thinking he has been stood up, Harry brings the dinner to Catherine. The next morning, Harry sees his girlfriend's car in the alley, and notices her hat on the beach next to a half-sunken hole. Police arrive, start digging and find an eyeball.
City councilwoman Harriett Crabbe is furious that the investigation has yielded no answers. Pearson is angry that Crabbe wants results, but does not want to pay for them.
Later, as Harry and Catherine walk along the beach, they decide the creature, or whatever it is, must be hiding below sea level where no one has searched. Harry investigates a deserted building and an abandoned area beneath the building. He finds nothing, although something watches him.
Later, a man named Mr. Hench searches with a metal detector near the piers, and he is sucked into the sand by the creature. The next day, Mrs. Hench reports her husband's disappearance to police. Shortly thereafter, a slime-covered Mr. Hench is found barely alive on the beach with his tongue ripped out.
While patrolling the deserted beach, Hoagy sees Mrs. Selden hiding under the piers, and when he gets out of his vehicle to help her, he is sucked into the sand, while she watches impassively.
Later, Catherine investigates the deserted building alone. Meanwhile, Harry and Detective also decide to search the building again, and arrive as Catherine discovers Hoagy's body. Officers swarm the area and discover the remains of 16 bodies.
That evening, Dr. Dimitrius arrives and suggests that the creature will return to its lair, but will leave if it sees anyone. Pearson sets up a surveillance camera, and has a demolition team rig the area so that Pearson can blow it up with one switch. Dimitrius is concerned about Pearson's plan because many creatures have regenerative abilities, and he wonders what will happen if they blow the creature up and the pieces regenerate? As they monitor the area, a giant worm-like creature emerges from the sand beneath the piers. Royko hits the switch and the creature explodes into thousands of dust-like bits.
The next day, Harry drives off with Catherine to take her home, and the beach is once again full of sun-worshipers. A little boy digs a sand castle while his mother makes sandwiches, but when she turns back, the boy is gone and only a small sinkhole in the sand remains. As she searches frantically for her son, more small sinkholes appear unnoticed in the sand up and down the crowded beach... strongly implying that Dr. Dimitrios was correct in his theory that the creature has the ability to reproduce itself from its severed pieces.