Emerging during hip-hop's late-1980s expansion, Insane Poetry ranked among the earliest groups to pursue horrorcore, issuing the underground single "Twelve Strokes Till Midnight" in 1988 before delivering their widely respected first album, Grim Reality, in 1992. The Los Angeles collective fused surreal imagery drawn from horror films with the stark, graphic approach of California gangsta rap, building a devoted following well before Esham or Gravediggaz entered the scene. Although membership shifted repeatedly, lead MC and producer Cyco—born Andrew Holiman—served as the unchanging force that sustained the project's identity once horrorcore largely remained an underground style into the 2000s.
Cyco assembled Insane Poetry in the closing years of the 1980s alongside DJ Streek and Shakespear the One-Man Riot after securing a DJ slot at Los Angeles hip-hop outlet KDAY. The 1988 single "Twelve Strokes Till Midnight" positioned Cyco among key industry figures, leading to a connection with Rodney O of the classic Los Angeles duo Rodney O & Joe Cooley. With Shakespear replaced by Em-Dee, Rodney O guided the group to Sir Mix-a-Lot's Nastymix Records, which issued Grim Reality. Although the album and its cult-favored track "How Ya Gonna Reason with a Psycho" earned strong notices, Nastymix—whose roster centered on club and party rap—struggled to market the group's intense aesthetic. After the label collapsed, IP, now featuring Pope in place of Em-Dee, recorded Blacc Plague in 1996 for React/Polygram, only to exit amid further disputes over marketing and backing.
Beyond scattered 12-inch releases and the three-track EP Let 'Em Know in 1999, IP maintained a low profile through the remainder of the 1990s. As the Los Angeles underground hip-hop community gained momentum in the early 2000s, Cyco revived the name, working alongside M-Boogie, Dilated Peoples, and Wake Up Show turntablist DJ Revolution. In 2001 he established Grim Reality Entertainment with producer Jason "JP" Pearl. Operating as the sole continuing member, IP released Faith in Chaos in 2003 and Fallen from Grace in 2007.