Fermat's Room

Fermat's Room is a 2007 Spanish thriller film directed by Luis Piedrahita and Rodrigo Sopeña. Three mathematicians and one inventor are invited to a house under the premise of solving a great enigma, and told to use pseudonyms based on famous historical mathematicians. At the house, they are trapped in a room. They must solve puzzles given by the host, who calls himself "Fermat", in order to escape the slowly closing walls of the room.

Synopsis from Wikipedia, CC BY-SA 4.0. Everything below written here.

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