Alternate dimensions, Mysterious plane crashes. Cannibalism. Zombies. Psychokinetic powers. Ancient tribal burial ground. Angry spirits. Hallucinations. Demonic Killers ... PSI Factor: Chronicles of the Paranormal. The complete Fourth Season will change the way you perceive reality. In 22 episodes, a fearless team of investigators from the covert Office of Scientific Investigation and Research (O.S.I.R.) explore bizarre, top-secret cases inspired by real, documented events. As O.S.I.R. agents face the supernatural in their search for clues, their quest for truth is often stranger than fiction itself.