Geoffrey Thorne. Writer: Magnum P.I.. Thorne was born in the United States., In 2000 Geoff quit a solid career as an actor (yes, cold turkey) to focus on being a professional writer. Breaking in as a Star Trek tie-in novelist and a finalist in the renowned Writers of the Future science fiction contest, Geoff went on to write for the hit TV series, Law & Order: Criminal Intent, Leverage and...