A woman becomes convinced that her husband is no longer really her husband. When it appears she has murdered him she claims she really didn't kill her husband - only his alien impostor.

A series of murders take place in front of witnesses who aren't even aware that someone has been killed. Pierce struggles with getting the FBI to accept his theory of mass blindness while he deals with the interference of a consultant.

In order to get information on a murder suspect, Daniel and Kate have to go undercover in an online gaming community. But being immersed in an imaginary universe is hardly the place for a schizophrenic like Daniel.

Parkinson patients start dying from defective implants used to control their symptoms. But even as he realizes the "malfunctions" may be a cover-up to murder, he also wonders if the miracle device could be a cure to his schizophrenia.

Moretti calls on Pierce to determine the credibility of a man's death-bed confession; Pierce and Moretti try to uncover the truth about a series of apparent homicides.

Daniel agrees to help a woman accused of killing a nurse in a state hospital even though it means going undercover inside an asylum. Once he's inside, his own hallucination has to compete against something the patients call "Creek".

In the conclusion of "Wounded", Kate goes on trial for the death of Sgt. Rickford. Donnie resigns his job to become her defense attorney even though Kate begins to doubt her own account of events and thinks she may in fact be guilty.

An autistic boy obsessed with trains, appears to have killed a security guard when he unexpectedly moved a train. Pierce realizes he actually prevented a railroad collision and that the dead guard may have been the victim of someone else.

Max Lewicki's estranged 16 year old brother shows up at Pierce's house one step ahead of the law. He eventually confesses to a murder but Pierce thinks that he only imagined it and tries to find the real killer.

Pierce receives a tip that the CIA might be assassinating U.S. citizens; one of Pierce's close friends is murdered; Moretti tries to overcome her trust issues.

Pierce's academic career is threatened when he hallucinates in class. Meanwhile, he, Moretti, and a RCMP officer track a serial killer who is stalking Pierce's former therapist. In the end, both he and Moretti face life-altering decisions.