Past Life follows investigative reporter Jason Frey (Aneurin Barnard), who reluctantly attends a hypnotism event with his pregnant wife, Claira (Pixie Lott). During the session, Jason witnesses a brutal murder—not as an observer, but through the eyes of a psychotic killer. Unable to shake the visions, he joins forces with the hypnotist (Jeremy Piven) to investigate a string of unsolved murders dating back to the 1980s. As they delve deeper into the mystery using past life regression, Jason unknowingly awakens the dormant instincts of a murderer whose story is far from over.