Keith Thornton (born 19 October 1966), better known by his stage name Kool Keith, is an American rapper from The Bronx, New York. Kool Keith began his rap career with the group Ultramagnetic MCs. After the release of their influential 1988 album Critical Beatdown, Thornton was reportedly institutionalized in Bellevue Hospital Center.However, he later said that the idea that he was institutionalized came from a flippant remark made during a stressful interview, and he never expected the story to become so well known.
After continuing with Ultramagnetic for two more albums (1992's Funk Your Head Up and 1993's The Four Horsemen), Thornton released his first notable solo single, "Earth People," in 1995, under the name Dr. Octagon. This was followed by the release of Dr. Octagonecologyst the following year. The album's production by Dan the Automator and Kutmasta Kurt, with scratching by DJ Qbert was acclaimed by critics, and the album was released nationally by DreamWorks Records in 1997, after an initial release on the smaller Bulk Recordings label (as, simply, Dr. Octagon)a year prior. DreamWorks also issued an instrumental version of the album, titled Instrumentalyst (Octagon Beats). Thornton followed the album with Sex Style in 1997, under the name Kool Keith.
In 1996, Thornton collaborated with Tim Dog for the single "The Industry is Wack," performing under the name Ultra - the album Big Time soon followed. In 1999, he released the album First Come, First Served under the name "Dr. Dooom", in which the album's main character killed off Dr. Octagon on the album's opening track. The same year, on August 10, 1999, Thornton released Black Elvis/Lost in Space. It peaked at #10 on the Billboard Heatseekers chart, #74 on the Top R&B/Hip-Hop Albums chart, and #180 on the Billboard 200, and stands as Thornton's most commercially-successful project to date.
On July 25, 2000, Thornton released the album Matthew. It peaked at #47 on the Billboard Heatseekers chart. The same year, Thornton collaborated with Ice-T, Marc Live, Black Silver and Pimp Rex for the album Pimp to Eat, under the group name Analog Brothers, with Keith performing as Keith Korg and Ice-T as Ice Oscillator.
On June 5, 2001, Thornton released the album Spankmaster on Esham's Gothom Records.It peaked at #16 on the Billboard Heatseekers chart, #11 on the Top Independent Albums chart and #48 on the Top R&B/Hip-Hop Albums chart.
In 2002, Thornton began recording The Resurrection of Dr. Octagon with producer Fanatik J, signing a contract with CMH Records to release the album, which was eventually completed without much input from Thornton, due to a falling out over contractual terms. Thornton, Marc Live and H-Bomb formed the group KHM, releasing the album Game on November 19, 2002, changing their name to "The Clayborne Family" by the release of their second album.
On October 12, 2004, Real Talk Entertainment issued the album Dr. Octagon Part 2. The album was discontinued by court order. On April 25, 2006, Thornton released the album Nogatco Rd. under the name Mr. Nogatco. On June 27, The Return of Dr. Octagon was released by OCD International, an imprint of CMH, advertised as the official follow-up to Dr. Octagonecologyst. Some critics felt that it was not as good as its predecessor.Thornton stated that he liked the album, but felt that it hurt his reputation as a musician. In August, Thornton performed under the Dr. Octagon billing, but did not acknowledge the release of the OCD album.
In 2007, Ultramagnetic MCs released the reunion album The Best Kept Secret.In 2009, Kool Keith released the concept album Tashan Dorrsett; a follow-up, The Legend of Tashan Dorrsett, followed two years later.In 2012, Kool Keith performed at the Gathering of the Juggalos. He has stated that he is considering retiring from music - this statement appears to be reinforced by the song "Goodbye Rap," found on his 2012 album release Love and Danger.
Thornton's fan site refers to his discography of roughly fifty album releases, most of which have been commercially released. Singles such as "Spectrum" continue to appear online under the artist's name, on sites such as SoundCloud and Spotify.