A psychiatric hospital is turned upside down when a mysterious drifter is admitted and assigned to room 316. Known only as John Doe, the other patients believe that he bears an uncanny resemblance to Jesus Christ. When he starts performing 'miracles', the residents begin to follow him as his disciples. This causes tension with the hospital administrators who are loathe to admit the patients are actually improving under John's guidance. They set out to expose him, leading to one final miracle that will change all their lives forever.