Set in 1920s New York City, the novel depicts the elderly Harlem houngan PaPa LaBas and his companion Black Herman racing against the Wallflower Order, an international conspiracy dedicated to monotheism and control, as they attempt to root out the cause of and deal with the "Jes Grew" virus, a personification of ragtime, jazz, polytheism, and freedom.
The United States' occupation of Haiti, attempts by whites to suppress jazz music, and the widespread belief that president Warren Harding had black ancestry are mingled with a plot in which the novel's hero, PaPa LaBas, searches for a mysterious book that has disappeared with black militant Abdul Sufi Hamid (whose name reflects that of the Harlem street corner radical preacher Sufi Abdul Hamid, a.k.a.
Other famous people who appear in the novel include the dance instructor Irene Castle, and the Harlem Renaissance authors James Weldon Johnson, Claude McKay, Wallace Thurman, Countee Cullen, W. E. B.
Du Bois, and a veiled reference to Malcolm X. Additionally, in his project of blending the "real" and the "invented," Reed, through Papa LaBas, recites a counter history of The Bible, whose content transforms the normative understanding of Judeo-Christian roots.
Featuring Osiris, Set, Moses and other important figures in both Egyptian and Judeo-Christian mythology, Reed re-imagines an entirely alternate past, evidenced by the Templar conflict that takes place in the novel.
Other classic mythological figures include Dionysus, who is portrayed as a follower of Osiris, and Faust, who receives his magic not through a deal with the devil but through connections with black Voodoo practicitioners.
The book's title is explained by a quote from the first edition of the American Heritage Dictionary deriving the phrase from Mandingo mā-mā-gyo-mbō meaning a "magician who makes the troubled spirits of ancestors go away.
Rather than stick to any semblance of a novel's conventions, Reed supplies us with a hodgepodge of hand-written letters, radio dispatches, photographs, various typefaces, drawings, and even footnotes.
James A. Snead sees the novel's structure as engaged of the African-American musical and rhetorical trope of "the cut", an interruption that disrupts the linear temporality of the work, looping back to an earlier textual moment.
[10] Pushing Gates' notion of "signifying pastiche" into the realm of the Afrofuturism, Alondra Nelson holds that Mumbo Jumbo imagines a version of African Diaspora that refuses to detach from tradition as it navigates modernity.
Additionally, the primary manifestation of this occurs in Papa LaBas' 30-page story of The Work (the original practice emanating from the text from which Jes Grew came) and its Egyptian roots.
With the framework of Jes Grew already established as a real phenomenon in the novel, Reed's 30-page history imagines a powerful origin and meaning that has, in the course of the African-American slavery experience, been strategically precluded.
"Jes Grew", Reed's "virus", alludes to the dissemination of uniquely African-American culture in the 1920s that "traversed the land in search of its Text: the lost liturgy seeking its litany".
In this instance Papa Labas taps into a similarity between the styles of music that Jes Grew needs to grow; '20s jazz and '70s funk share an aesthetic that calls people to dance.