Nightmares Come at Night(1970)

Diana Lorys, Collette Jack and Soledad Miranda star in this sexy thriller about two alluring dancers, Cincia and Anne, who embark on an erotically charged partnership. But when Anne starts to have nightmares that feature her as a murderous killer, she begins to lose her grip on reality. Or is reality merely rearing its ugly head in her dreams? She's determined find out what's causing this turmoil before something deadly happens.