The Witch Who Came from the Sea

This one's a real weirdie. It's unique, surreal and genuinely disturbing, and Millie Perkins gives a memorably intense and bizarre performance as Molly. It goes out of its way to shock the viewer, and largely succeeds. It also features the single most upsetting childhood trauma flashback I've ever seen.

It's probably too much for most people's tastes, but if you enjoy flawed one-of-a-kind low budget '70s horror, it's worth a look if you can find it. I am a bit dubious about the exploitative way it uses the subject of child abuse device to shock and disturb the viewer, so be warned.