Fermat's Room
Now this is the kind of horror I like: bizarre! And even better is its Spanish! I can't wait for this!
four mathematicians who have never met before are invited by a mysterious host to spend a weekend in an abandoned house, to try and solve a great numerical enigma. However, they soon realise that each time they fail to solve a puzzle the room they are in, starts to shrink. Unless they quickly find out why someone is trying to murder them all, they will soon be crushed to death.