K-PAX
When he claims he is an alien from a planet called 'K-PAX' and traveled to Earth via 'light rays', a man calling himself "Prot" (Kevin Spacey) is handed over to a New York hospital psychiatric ward. A Manhattan psychiatrist, Mark Powell (Jeff Bridges), is given the task of treating and "curing" Prot of his supposed delusions. Right from the first psychiatric session, Dr. Powell begins to discover Prot's uncanny abilities and immense knowledge. As the story develops, Dr. Powell becomes quite attached to Prot, and starts to believe his seemingly impossible claims. Prot even baffles some of the foremost astrophysicists with his knowledge of science and astronomy.
Once Prot displays seemingly violent behavior at Dr. Powell's house, Dr. Powell decides to regress him to find out more about Prot's past. Because Prot has promised he will leave Earth on July 27, it's a race against time for Dr. Powell to find out the real identity behind the enigmatic Prot. Prot also promises that he will take one of the ward's patients with him, and encourages an essay competition among them to determine his choice. Unfortunately, Dr. Powell is only able to find out about the human whose body Prot has been occupying who, according to Prot, was his childhood friend who witnessed the murder of his own family.
After Prot, while under hypnotic regression, reveals the emotionally painful incident which occurred at his home after coming home after working as a "cattle knocker," Powell conducts extensive research which points to a small town in New Mexico. His investigation leads him to the criminal case of Robert Porter, who suffered the exact circumstances Prot revealed in a remarkably similar location that Prot had described in detail.
Upon returning to the hospital, Powell confronts Prot with a photograph of himself labeled 'Robert Porter,' which Prot dismisses. However, he asks Powell to "take care of him" (Robert).
On July 27, Powell races to Prot's room and after initially believing he has vanished, he finds him under the bed. At the same moment, the patients of the mental facility realize that Bess, arguably the quietest and least selfish of any of them, is missing, presumably never to be seen again.
Sometime later, Powell is seen caring for Porter who is now in a catatonic state. The film leaves the viewer wondering whether Prot really was an extraterrestrial from K-PAX who took over Porter's human host to save his life—or whether Porter really is an insane man whose catatonia is a result of being forced to confront his delusions.
