Night Tide (1961)

Night Tide (1961), directed by Curtis Harrington.

A lonely sailer falls in love with a strange woman working as a carnival mermaid at the pier. Too late, he discovers the police are watching her -- two of her earlier boyfriends drowned. She thinks she is one of the "sea people": a siren who lures sailors to their deaths. Oddly enough, other people believe it, too. He begins having lurid nightmares...

A micro-budget, minimalist production with both pro and amateur cast. It has a bit of the Twilight Zone and The Outer Limits (1963) ambience of the period, and that dreamy off-kilter mood of Carnival of Souls (1962). More than anything it seems like a return to the Val Lewton thrillers of the 1940s.

Like Psycho (1960) it wraps up with a rational (or rationalizing?) explanation.

Dennis Hopper was an unusual choice for the lead (his first). As warm and friendly as he tries to be, there is always a dangerous unreliability to his persona. You expect him to go all pervy and transform into a giggling sadist at any moment.

David Raksin score. Hopper did his own scuba-diving. Roger Corman helped with financing, such as it was, but the independent production had many money problems.

There seem to be several DVD versions. The one I got from Netflix is 4:3 letterboxed but has a late 1990s commentary track by Hopper and the director. Harrington confirms he was thinking of Val Lewton and Cat People (1942).

Also available online for free: Night Tide. I haven't watched that version.