Magnum, P.I. is an American television showstarring Tom Selleck as Thomas Magnum, a private investigator living in Oahu, Hawaii. The series ran from 1980 to 1988 in first-run broadcast on the American CBS television network. According to the Nielsen Ratings, Magnum, P.I. consistently ranked in the top twenty U.S. television programs during the first five years that the series was originally telecast in the United States. Originally appearing in a prime time American network timeslot of 8 p.m. Eastern on Thursdays,Magnum, P.I. was one of the highest-rated shows on U.S. television.
Thomas Sullivan Magnum lives and resides in the 'guest house' of a posh, 200-acre (0.81 km2) beachfront estate, known as Robin's Nest, in Hawaii, at the invitation of its owner, Robin Masters, the celebrated-but-never-seen author of several dozen lurid novels. Ostensibly this is quid pro quo for Magnum's services based upon Magnum's claimed expertise in security; the pilot suggests Magnum also did Masters a favor of some kind. [wikipedia]