Fermat's Room

If you’re the sort of smart cinema patron who loved Cube and wolfed down Pi, this fiendishly clever math horror from Spain might as well be called Super Fun Happy Slide.
The set-up is a real doozy – five mathematically minded boffins receive mysterious invitations to a remote barn where, with a nod to Saw, they must solve tricky sums in order to prevent trick walls from closing in and making them into brainy pate.
Who has brought them here? And why? As panic sets in, all manner of terrible secrets are revealed. What’s the deal with the cool old guy? Or the hydraulics expert? Or the protégée who was sabotaged when his written resolution of Goldbach’s Conjecture disappeared from his dorm?
Some of the puzzles are unworthy of finer minds and the entire conceit could have been ripped from a creaky Agatha Christie novel, but co-directors Luis Piedrahita and Rodrigo Sopena do tremendous work; the thrills are constant, the tension is high and the characters are just annoying enough to have you shouting at the screen. Now that’s good watching.