The late Curtis Harrington’s darkly atmospheric Night Tide (1961) was the first film to star a young Dennis Hopper. The plot revolves around a sailer (Hopper) who has an affair with a mysterious and beautiful woman (the gorgeous Linda Lawson) who portrays a mermaid at a sideshow on the Venice Beach boardwalk. The sailor begins to suspect that his lover is an actual mermaid who commits ritual murders of her lovers during the full moon.
 

 
Witchy artist Marjorie Cameron, who memorably played the Scarlet Woman in Kenneth Anger’s Inauguration of the Pleasure Dome (Harrington shot Anger’s Puce Moment and appeared in Pleasure Dome as well) has a small but pivotal role as a super intense woman who seems to hold a strange and fearsome power over Lawson’s character. There is also a fantastic jazzy/beatniky soundtrack by David Raksin (who worked on the soundtrack to Modern Times with Charlie Chaplin and composed the haunting theme to Otto Preminger’s Laura which became one of the most frequently recorded jazz standards).
 

 
Night Tide—which many people place in same category as Carnival of Souls or Val Lewton’s Cat People (I can see that) was restored by the Academy Film Archive in 2007. A Blu-ray release of the film struck from a 35mm print came out in 2015 from Kino Lorber.