# Magnum, P.I.
**Magnum, P.I.** is an American action drama series about [Thomas Magnum](https://www.edgepedia.org/thomas-magnum), a former Naval Intelligence officer who resigns his commission to work as a private investigator on the north shore of Oahu, Hawaii, starring [Tom Selleck](https://www.edgepedia.org/tom-selleck).[1](https://www.hallmarkmystery.com/magnum-pi/about-magnum-pi) • [2](https://www.tvsa.co.za/shows/viewshowabout.aspx?showid=2779) Created by [Donald P. Bellisario](https://www.edgepedia.org/donald-p-bellisario), the original series ran on CBS from 1980 to 1988 in 162 hour-long episodes in eight seasons.[2](https://www.tvsa.co.za/shows/viewshowabout.aspx?showid=2779) A reboot with a new cast premiered on CBS in September 2018 and later moved to NBC.[3](https://www.paramountpressexpress.com/cbs-entertainment/shows/magnum-pi) • [4](https://www.nbc.com/magnum-pi/about)
| Key fact | Detail |
|---|---|
| Original run | CBS, 1980–1988; 162 hour-long episodes in eight seasons, created by Donald P. Bellisario[2](https://www.tvsa.co.za/shows/viewshowabout.aspx?showid=2779) |
| Premise | Former Naval Intelligence officer Thomas Magnum becomes a private investigator on Oahu's north shore[1](https://www.hallmarkmystery.com/magnum-pi/about-magnum-pi) |
| Ratings peak | Top-20 ranking for each of its first five broadcast years; season 3 (1982–83) averaged 18.80 million viewers at rank #4[5](https://www.tvencyclopedia.org/tv-encyclopedia-10/magnum-pi) • [6](https://culture.fandom.com/wiki/Magnum,_P.I.) |
| Signature setup | Magnum lives at the North Shore estate of novelist Robin Masters and drives the estate's Ferrari[7](https://magnum-mania.com/Articles/Magnum_PI_Writers_Bible.pdf) |
| Vietnam theme | One of the first series to regularly explore the Vietnam War's impact on the American cultural psyche[5](https://www.tvencyclopedia.org/tv-encyclopedia-10/magnum-pi) |
| Reboot | Premiered on CBS September 24, 2018, starring Jay Hernandez, Perdita Weeks, Zachary Knighton, and Stephen Hill; later seasons streamed on Paramount+ and the series moved to NBC[3](https://www.paramountpressexpress.com/cbs-entertainment/shows/magnum-pi) • [4](https://www.nbc.com/magnum-pi/about) |
## Original series (1980–1988)
CBS had the series developed to make use of the extensive production facilities built in Hawaii during the 1970s for the police procedural *Hawaii Five-O*.[5](https://www.tvencyclopedia.org/tv-encyclopedia-10/magnum-pi) The show aired on CBS from 1980 through 1988 as a permutation of the hard-boiled detective genre.[5](https://www.tvencyclopedia.org/tv-encyclopedia-10/magnum-pi) Season 1 ran from December 11, 1980 to April 16, 1981 with 18 episodes, averaging 16.77 million viewers and ranking #14.[6](https://culture.fandom.com/wiki/Magnum,_P.I.) For most of its run the series aired Thursdays at 8:00–9:00 pm, moving to Wednesday 9:00–10:00 pm for seasons 7 and 8.[6](https://culture.fandom.com/wiki/Magnum,_P.I.)
Sources disagree on the exact end of the run: one reference listing says the series ended in February 1988,[2](https://www.tvsa.co.za/shows/viewshowabout.aspx?showid=2779) while a season table gives season 8 as running October 7, 1987 to May 1, 1988 with 13 episodes.[6](https://culture.fandom.com/wiki/Magnum,_P.I.)
## Characters and mythology
**The estate arrangement.** The series' writers' bible establishes that Thomas Sullivan Magnum resides at the opulent North Shore estate of Robin Masters, a famous "pulp" novelist, and that Magnum gets to drive the estate's Ferrari, a living arrangement unlike the mobile, working-class setups of contemporaries such as *The Rockford Files*.[7](https://magnum-mania.com/Articles/Magnum_PI_Writers_Bible.pdf)
**The supporting cast.** In the reboot, Juliet Higgins is a disavowed MI:6 agent serving as the estate's "majordomo", TC is a former Marine chopper pilot running Island Hoppers, and Rick is a former Marine door-gunner who runs a nightclub, with Detective Gordon Katsumoto as a recurring foil.[3](https://www.paramountpressexpress.com/cbs-entertainment/shows/magnum-pi)
**Vietnam.** Among the earliest shows to address on a routine basis how the [Vietnam War](https://www.edgepedia.org/vietnam-war) had shaped the American cultural consciousness, the series drew many storylines from Magnum's wartime past.[5](https://www.tvencyclopedia.org/tv-encyclopedia-10/magnum-pi) Co-creator Donald P. Bellisario discussed incorporating the war into the series in a Television Academy oral history interview.[8](https://interviews.televisionacademy.com/interviews/donald-p-bellisario) Critics have noted that in dealing with this past, the series both criticized and recuperated the involvement of the United States in Vietnam, producing conflicting ideological perspectives across its run.[5](https://www.tvencyclopedia.org/tv-encyclopedia-10/magnum-pi)
## Production and Hawaiian setting
The choice of Hawaii was structural, not incidental: the network developed the series specifically to keep the *Hawaii Five-O* facilities in use, and part of its success stemmed from combining familiar hard-boiled action with an exotic locale.[5](https://www.tvencyclopedia.org/tv-encyclopedia-10/magnum-pi) The Guardian's retrospective describes the resulting character as a Vietnam vet-turned-private eye who could handle a gun if required but was happier loafing around in too-tight shorts and a Hawaiian shirt, played by Tom Selleck as an avatar of rugged masculinity eager to show comic range.[9](https://www.theguardian.com/tv-and-radio/2018/oct/08/how-magnum-pi-genre-mashing-met-a-hairy-end)
## Reception and ratings
For the first five years the series was broadcast, it ranked in the top 20 shows each year.[5](https://www.tvencyclopedia.org/tv-encyclopedia-10/magnum-pi) The season table shows a peak at #4 in 1982–83 with 18.80 million viewers, a fall to #46 by season 6 (1985–86), a recovery to #34 in season 7 after the move to Wednesday nights, and #40 for the 13-episode final season.[6](https://culture.fandom.com/wiki/Magnum,_P.I.)
The series' success opened the door for later Vietnam-themed dramas such as *Tour of Duty* and *China Beach*, which, though not as popular, showed that room existed in mainstream broadcasting for discussion of the war's emotional and political wounds.[5](https://www.tvencyclopedia.org/tv-encyclopedia-10/magnum-pi)
## 2018 reboot
The reboot offers a modern reimagining of the story, which follows Thomas Magnum, a former Navy SEAL with a distinguished record who, once back home from Afghanistan, puts his military abilities to use as a private investigator.[3](https://www.paramountpressexpress.com/cbs-entertainment/shows/magnum-pi) Magnum lives in a guest cottage on Robin's Nest, working as a security consultant.[3](https://www.paramountpressexpress.com/cbs-entertainment/shows/magnum-pi) It premiered Monday, September 24, 2018, in the 9:00–10:00 PM ET/PT slot on CBS, starring [Jay Hernandez](https://www.edgepedia.org/jay-hernandez), Perdita Weeks, Zachary Knighton, and Stephen Hill.[3](https://www.paramountpressexpress.com/cbs-entertainment/shows/magnum-pi) The fourth season began Friday, October 1, 2021, on CBS with streaming on Paramount+.[3](https://www.paramountpressexpress.com/cbs-entertainment/shows/magnum-pi) NBC maintains the series' later official show page, consistent with the reboot's move to NBC after its CBS run.[4](https://www.nbc.com/magnum-pi/about)
## Genre context and legacy
The series departed from the stock "crime of the week" format: discussion of events from previous episodes continually popped up, constructing memory as an integral element of the series' franchise, without adopting the open-ended strategies of prime-time soap operas.[5](https://www.tvencyclopedia.org/tv-encyclopedia-10/magnum-pi) A planned crossover with *Murder, She Wrote* illustrated how the show's genre-mash identity collided with other series' formats, contributing to an abrupt end to that experiment.[9](https://www.theguardian.com/tv-and-radio/2018/oct/08/how-magnum-pi-genre-mashing-met-a-hairy-end) As a permutation of the hard-boiled detective genre transplanted to Hawaii, the series aired on CBS from 1980 through 1988.[5](https://www.tvencyclopedia.org/tv-encyclopedia-10/magnum-pi)
## References
1. [Magnum P.I. – About, Hallmark Mystery](https://www.hallmarkmystery.com/magnum-pi/about-magnum-pi)
2. [Magnum, P.I. – About the Show, TVSA](https://www.tvsa.co.za/shows/viewshowabout.aspx?showid=2779)
3. [Magnum P.I. – Paramount Press Express, CBS Entertainment](https://www.paramountpressexpress.com/cbs-entertainment/shows/magnum-pi)
4. [Magnum P.I. – NBC.com](https://www.nbc.com/magnum-pi/about)
5. [Magnum, P.I. – Encyclopedia of TV & Radio](https://www.tvencyclopedia.org/tv-encyclopedia-10/magnum-pi)
6. [Magnum, P.I. – ratings/seasons table, Culture Fandom](https://culture.fandom.com/wiki/Magnum,_P.I.)
7. [Magnum P.I. Writers' Bible (fan-archived production document)](https://magnum-mania.com/Articles/Magnum_PI_Writers_Bible.pdf)
8. [Donald P. Bellisario – Television Academy Interviews](https://interviews.televisionacademy.com/interviews/donald-p-bellisario)
9. [How Magnum PI's genre-mash met a hairy end, The Guardian (2018)](https://www.theguardian.com/tv-and-radio/2018/oct/08/how-magnum-pi-genre-mashing-met-a-hairy-end)
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*Topic: Encyclopedia › Arts and culture › Screen and stage › Film and television › Series and fictional screen worlds › Scripted television and comedy series › Genre and subject-scripted series › Crime, police, and detective series › American crime series › Private detective and mystery series*
*Initially written Sep 17, 2026 · Reviewed: Oct 25, 2026 · Edited: Oct 15, 2026; Oct 25, 2026 · Last review: Oct 25, 2026*
*Copyright 2026 EdgeChat AI, a subsidiary of Biostate AI.*
License: Edgepedia Community License 1.0, https://www.edgepedia.org/edgepedia/license