A onetime psychiatric patient at Bellevue, Keith's lyrical thematics remained as free-flowing here as they ever were with the N.Y. trio, connecting up complex meters with fierce, layers-deep metaphors and veiled criticisms of those who "water down the sound that comes from the ghetto." His own debut single, "Earth People" by Dr. Octagon, was quietly released in late 1995 on the San Francisco-based Bulk Recordings, and the track spread like wildfire through the hip-hop underground, as did the subsequent self-titled full-length released the following year.

Featuring internationally renowned DJ Q-Bert (also of the Invisibl Skratch Piklz) on turntables, as well as the Automator and DJ Shadow behind the boards, Dr. Octagonecologyst's left-field fusion of sound collage, fierce turntable work, and bizarre, impressionistic rapping found audiences in the most unlikely of places, from hardcore hip-hop heads to jaded rock critics. Although a somewhat sophomoric preoccupation with body parts and scatology tended to dominate the album, Keith's complex weave of associations and shifting references is quite often amazing in its intricacy. The record found its way to the U.K.-based abstract hip-hop imprint Mo'Wax (for whom Shadow also recorded) in mid-1996 and was licensed by the label for European release (Mo'Wax also released a DJ-friendly instrumental version of the album titled, appropriately, The Instrumentalyst: Octagon Beats). The widespread popularity of the album eventually landed Keith at Geffen splinter Dreamworks in 1997; the label gave Dr. Octagonecologyst its third release mid-year, adding a number of bonus cuts.

In early 1999, however, Keith's alter ego Dr. Dooom unfortunately "killed off" Dr. Octagon on the opening track of the 1999 album First Come, First Served (released on Thornton's own Funky Ass label). Kool Keith signed to Ruffhouse/MCA for his second album under that alias, 1999's Black Elvis/Lost in Space. Records released as Kool Keith followed in 2000 (Matthew) and 2001 (Spankmaster), while the 2002 collaboration Game appeared as KHM (Kool Keith plus H-Bomb and Marc Live). A variety of releases from Keith's myriad alter egos came in the following years, including Kool Keith Presents Thee Undatakerz and Diesel Truckers, the latter of which he did with KutMasta Kurt and both of which were issued in 2004, and the 2006 records Nogatco Rd. and the long-awaited Return of Dr. Octagon, which was produced by One Watt Sun and recorded in a 12th century tower in Prague, Berlin, and Australia. ~ Sean Cooper