He began performing at open mic events while wearing a metal mask resembling that of the Marvel Comics supervillain Doctor Doom, who is depicted on the cover of his 1999 debut solo album Operation: Doomsday.

Madvillainy (2004), recorded with the producer Madlib under the name Madvillain, is often cited as Dumile's magnum opus and is regarded as a landmark album in hip hop.

Though he lived most of his life in the United States, Dumile never gained American citizenship; in 2010, he was denied reentry after returning from an international tour for his sixth and final solo album, Born Like This (2009).

[10] As a child, Dumile moved with his family to Long Beach, New York,[11] where he grew up in a black nationalist Muslim household as part of the Five-Percent Nation.

[12] He said he had no memory of his London childhood and defined himself as a "New York nigga",[9] but remained a British citizen his entire life and never gained American citizenship.

[14][15] As a child, he was a fan and collector of comic books and earned the nickname "Doom" (a phonetic play on the name Dumile) among friends and family.

[16][17] Under the name Zev Love X,[18] Dumile formed the hip hop group KMD in 1988 with his younger brother DJ Subroc and Rodan, who was later replaced by Onyx the Birthstone Kid.

[21] On April 23, 1993, just before the release of the second KMD album, Black Bastards,[19] Subroc was struck by a car and killed while crossing the Long Island Expressway.

[24] KMD was dropped by Elektra and the album went unreleased due to its controversial cover art,[20] which featured a cartoon of a stereotypical pickaninny or sambo character being hanged.

[25] After his brother's death, Dumile retreated from the hip hop scene from 1994 to 1997, living "damn near homeless, walking the streets of Manhattan, sleeping on benches".

[26] In 1997 or 1998,[b] Dumile began freestyling incognito at open-mic events at the Nuyorican Poets Café in Manhattan, obscuring his face by putting tights over his head.

[30][31] Dumile's collaborators on Operation: Doomsday included fellow members of the Monsta Island Czars collective, for which each artist took on the persona of a monster from the Godzilla films.

[39][40] In Pitchfork, Mark Martelli described Take Me to Your Leader as close to a concept album, noting how it lays out the "mythos" of the eponymous King Geedorah.

Club that VV:2, coming as it did after the commercial and critical success of Madvillainy, represented an unusual career choice for Dumile whereby he went "deeper underground" instead of embracing wider fame.

Around this time, he also appeared in a voice role in the Adult Swim animated series Perfect Hair Forever as Sherman the giraffe.

The album, released on October 11, 2005, by Epitaph and Lex, was developed in collaboration with Cartoon Network's Adult Swim and featured voice actors and characters from its programs (mostly Aqua Teen Hunger Force).

[51] Critic Chris Vognar, discussing the role of comedy in hip hop, argued that "Doom and Danger exemplify an absurdist strain in recent independent hip-hop, a willingness to embrace the nerdy without a heavy cloak of irony".

[60] In a largely favorable review for Pitchfork, Nate Patrin cast the album as a return to form for Dumile, following a period of limited output.

[61] He observed that Dumile's lyrics and flow—"a focused rasp that's subtly grown slightly more ragged and intense"—were darker than on earlier records.

[71] Reviews of Key to the Kuffs in Pitchfork and Fact emphasized its references to Dumile's "exile" in the United Kingdom,[72][73] while Resident Advisor noted its play on Britishisms in tracks like "Guv'nor".

[83] Aside from the album with Czarface, Dumile's musical output in the final three years of his life was limited to one-off guest appearances on other artists' tracks.

[26] According to an obituary in The Ringer, his flow was "loose and conversational, but delivered with technical precision", and his use of rhyme and meter eclipsed that of Big Pun and Eminem.

[94] His signature mask was similar to that of Doctor Doom,[28] who is depicted rapping on the cover of Dumile's 1999 debut album Operation: Doomsday.

[97] Academic Hershini Bhana Young argued that, by appropriating the Doctor Doom mask, Dumile "positions himself as enemy, not only of the music industry but also of dominant constructions of identity that relegate him as a black man to second-class citizenship".

"[92] In November 2019, during his performance at the Adult Swim Festival, the electronic artist Flying Lotus announced that he would be joined onstage by Dumile.

"[101] The English musician Thom Yorke, who twice collaborated with Dumile, wrote: "He was a massive inspiration to so many of us, changed things... For me the way he put words was often shocking in its genius, using stream of consciousness in a way I'd never heard before.

[12] Dumile's father taught him about pan-African history, including historical figures such as Marcus Garvey and Elijah Muhammad, which he strove to impart on his peers.

[109] In their music, the members of KMD professed a religious message based on tenets of Nuwaubianism, which Dumile distinguished from Five-Percent beliefs in an early interview.

[111] By 2000, though he was no longer as strictly observant, Dumile still participated in Nuwaubian events such as the Savior's Day celebration at the Tama-Re compound in Georgia and held a positive opinion of the community.

[114] It was only his second international tour, and he had previously avoided leaving the United States; he had believed he would be able to secure re-entry based on his long-term residency and family connections.