Season 5, Episode 11
SAM AND DEAN CHECK INTO A MENTAL HOSPITAL
A former hunter named Martin (guest star), who is currently institutionalized, calls Sam (Jared Padalecki) and Dean (Jensen Ackles) for help investigating a case in the mental hospital. The brothers get themselves admitted as patients to check out the mysterious monster that is attacking the patients, but their incarceration pushes both to the breaking point as they unleash their inner demons against each other.
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