Escalofrío (1978)

Andy and Thelma are a couple living in Madrid. One day they took their dog out to play. On the way, they meet a pair of strange lovers Bruno and Anne and invite Andy and Thelma to the country house. At night, because of the storm, they decided to stay there for the night. They came up with a vision version to communicate with the undead, but soon there was a conflict: Thelma had sex with Andy's brother, and Anne blamed him for Bruno's suicide-but this was just the beginning of the nightmare that would haunt them in the house.