Siffre (2017)

Siffre is based on the story of Michel Siffre, a french scientist who in 1962 conducted one of the first solitary isolation experiments. 375 feet underground, with no clocks or daylight, Michel spent 63 days living completely out of time. On one day of his experiment, a rockfall causes his interior power to go off, he must restore power in order to call the base team to make sure they are safe, and find a sense of security again whilst alone underground.