Mistakes

Toward the beginning, when the characters wonder aloud what the rumbling noise is, someone suggests that it's the ventilation system, to which Rennes responds "No vents." However, in the passages between rooms there are panels with ventilation slits in them (which you can plainly see even as Rennes says the line), and it's pretty impossible that the characteristically level-headed and observant Rennes wouldn't have noticed that. See more...

Trivia

All the characters in the movie are named after famous prisons around the world - Holloway, Wren, Leavenworth, San Quentin, etc. The characters match the prison types too - Alderson never meets the group, and isolation is the major form of punishment at Alderson Prison in West Virginia. Dr. Hollaway is a female doctor, and Holloway Prison is a women's prison in England, Kazan is autistic, and Kazan Prison is Russia is a "disorganized" prison, etc. See more...

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