After a plane crash, only a few of the 109 passengers survived. Psychologist Claire (Anne Hathaway) was sent by her mentor to provide psychological treatment to the survivors, but she found that she gradually fell in love with one of the survivors, Eric (Patrick Wilson), a former vice president of a securities company. At the same time, Claire found that there were often people monitoring outside the clinic, she was being followed, patients mysteriously disappeared, and even airline staff came to threaten her not to meddle in other people's business. This made Claire suspect that the airline deliberately used operational errors to cover up the fact of mechanical failure to avoid investigation, and then took action against the surviving passengers who discovered the truth. As Claire and Eric's relationship deepened, the number of patients became fewer and fewer, Claire lost contact with her sister's family, and even her own safety was threatened...