The Valet (Manuel Rosón) enters a hotel room with Joseph Garcin (Morgan Sterne) in tow. The windowless room has a single entrance and no mirrors. Two women, Inès Serrano (Viveca Lindfors) and Estelle Rigault (Rita Gam), are then led in; afterwards, the Valet leaves and locks the door. Realising that they are in hell, the trio expects to be tortured; however, no torturer is forthcoming. While waiting, they strike up a conversation and discuss each other's sins, desires, and unpleasant memories. Adaptation of the play by Jean-Paul Sartre.

"Though not given a New York showing until 1935, V. I. Pudovkin's Mechanics of the Brain (Mekhanika Golovnovo Mozga) was written and directed by Pudovkin in 1926. A full year in the making, this scientific documentary concentrates on the behavioral studies conducted by Prof. Ivan Pavlov. The laboratory dogs used in Pavlov's research don't seem too happy about it, and as a result this film might be hard to take for the more sensitive viewers (the vivisection sequence is particularly rough). The progress of the research is detailed with charts and graphs, hardly the "cinematic" touches one might expect from Pudovkin. Interestingly, Mechanics of the Brains was released two years before the results of Pavlov's studies were printed in book form."