Night Tide is a 1961 horror-thriller movie directed by Curtis Harrington. The main character of the movie is Johnny Drake, who is a sailor on shore leave. Johnny visits a seaside carnival and becomes entranced by a mysterious woman named Mora, who works as a mermaid in a sideshow attraction. They quickly develop mutual feelings for each other, but Detective Lieutenant Murdoch warns Johnny that Mora is a jinx who has already been linked to the deaths of her two previous boyfriends.
Despite the warnings, Johnny continues to pursue a relationship with Mora, and she reciprocates his feelings. However, strange things start happening, and Johnny's suspicion grows that Mora might not be what she appears to be. He discovers that she is a member of an ancient race of sea creatures called the Nereids, who were believed to have drowned sailors to fulfill their desires.
As Johnny delves further into the mystery surrounding Mora, he begins to realize that he may have fallen in love with a creature of the sea and that his life may be in danger. The movie builds up tension and mystery, culminating in a thrilling and unexpected climax. Night Tide is a highly atmospheric and suspenseful movie that stands the test of time, showcasing Harrington's talent for blending horror, fantasy, and suspenseful drama into a compelling story.