Near a small East Coast beach town, a boat dumps a 55-gallon metal drum labeled "Danger Radioactive Waste" into the ocean.

They quarrel and Tina leaves him and begins flirting with Mike, the leader of a motorcycle gang, as Hank talks with Dr. Gavin's daughter Elaine.

As Hank and Elaine attend an evening dance party at the beach, one of the monsters stalks two young women who are walking through town.

Frustrated when the women are picked up by a passing automobile, the monster attacks female mannequins on display in a storefront window, in the process severing its arm.

Following a montage of additional women being attacked and killed, the police initiate unsuccessful searches for the monsters by tracking the latter's trail of radioactive water.

As Hank drives to New York City to obtain a supply of metallic sodium, Elaine performs her own search for the monsters at a local quarry, near where the female travelers were killed.

His career began as an actor, working at the Los Angeles State College, appearing as an extra in films such as Stalag 17 and The Wild One.

After moving to New York to act professionally, he worked as an assistant director in exploitation films, including Satan in High Heels.

The biker gang in the film was portrayed by the Charter Oak Motorcycle Club (described as being "affiliated with, but ... a step beneath, the Hells Angels")[3] of Riverside, Connecticut.

Ray Dennis Steckler's The Incredibly Strange Creatures Who Stopped Living and Became Mixed-Up Zombies also made the same claim a few months earlier.

[5] Edward Earle Marsh (aka Zebedy Colt) composed the film's soundtrack; Wilfred Holcombe was credited as the musical director.

Marsh and Holcombe wrote three songs that were performed in the film: "Joy Ride", "The Zombie Stomp" and "You Are Not a Summer Love".

[20][21] The Horror of Party Beach was featured in an eighth-season (1997) episode of Mystery Science Theater 3000 (MST3K), an American television comedy series.

Factory released the MST3K episode as part of the "Volume XXXVII" DVD collection of the series, along with The Human Duplicators, Escape from the Bronx, and Invasion of the Neptune Men.

[22] Paul Chaplin stated that the writing team for the show found The Del-Aires to be one of the few bright spots in the movie, and despite their mocking, they thought the group to be a "darn good band.