The Horror of Party Beach (working title Invasion of the Zombies) is a 1964 American horror film in the beach party genre, directed by B-movie maven Del Tenney, which Tenney himself describes as “a take-off on beach parties and musicals”. The original theatrical release of the film paired it with another Del Tenney feature, The Curse of the Living Corpse, in a studio-sanctioned double feature.
A small East Coast beach town experiences a wave of attacks from creatures derived from water plants and dead human tissue mutated from radioactive waste. The monsters coalesced into humanoid form by attaching themselves to skeletons in a shipwreck. They immediately proceed to hunt down and kill (mostly young) women, as is common in the horror films of this era. Despite the murders committed by the monsters, young women in large numbers conveniently keep returning to the area for activities like slumber parties. Trying to stop the monsters are scientist Dr. Gavin, his young-adult daughter Elaine, and her boyfriend (and Dr. Gavin’s employee) Hank Green, with some unexpected assistance from housekeeper Eulabelle and metallic sodium.
The Horror of Party Beach was included as one of the choices in the 1978 book The Fifty Worst Films of All Time.
Movie-mocking television series Mystery Science Theater 3000 featured The Horror of Party Beach in one of its season 8 episodes in 1997.