Revealing mistake: When Doctor Haier is explaining the operation to the captives, he says he'll sever the ligament in the knee. However, around the 1-hour mark when the captives are walking by the pool, you can see the rear woman's leg raise her left foot off the floor when she moves forward, showing she still has control over her knee.
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Suggested correction: He explicitly states that the ligament severed prevents the knee from being straightened, not bent.
