It is 1920 and the Jes Grew phenomenon is spreading, first taking over New Orleans, then Chicago, and making its way to New York. Jes Grew is Blackness incarnate, manifested in music, singing, dancing, sex, and Life itself. It disturbs the pillars of Western Civilization, which is committed to stamping it out.
The resistance is the Atonists, particularly the Teutonics, an ancient secret society, and their militant wing is the Wallflower Order. They most recently tried to obliterate Jes Grew in the 1890s but did not do such a great job. Their plan now is to install an anti-Jes-Grew president, Warren Harding, and groom a Talking Android who will spread the message that Jes Grew is actually anti-Black, getting people to turn against it.
The Atonists not only have Jes Grew to deal with but also the Mu’tafikah, art “thieves” committed to taking what the West looted for their museums and sending it back where it belongs.
The man spearheading the effort to spread Jes Grew and destroy its enemies is astro-detective PaPa LaBas, a powerful obeah-man who holds court at the Mumbo Jumbo Kathedral in Harlem. He works with Berbelang, who has recently moved to the Mu’tafikah, Earline, and Charlotte, who has left to go to the stage.
At a party one evening, LaBas connects with Black Herman, a noted occultist. The two speak with the irascible Abdul Hamid, a publisher and Black Nationalist, who chastises them for filling people’s heads with nonsense. They listen to him and challenge his views, but they make no headway. Abdul leaves, saying he has to translate a book that will shake everyone up.
Hinckle Von Hampton is an elegantly dressed old white man who is secretly thousands of years old. He is an original Knights Templar and is here to agitate the Order. He does so by publishing an account of their war in Haiti, which was supposed to be a secret. He is called into the Hierophant 1’s office, where the Hierophant demands the sacred Book he knows Hinckle possesses. If this Book unites with its music, Jes Grew will be unstoppable.
Hinckle says he does not have it and has sent it around in a chain with fourteen different people. Only he can bring it together, which he promises to do if the Hierophant will give the Templars back their power. The Hierophant is reluctant but has no choice.
Hinckle’s first part of the plan is to publish a magazine, The Benign Monster, which will give him the facade of being a Negrophile. The magazine became infamous and is banned as pornography in some cities. Hinckle hires a newcomer to the city, Woodrow Wilson Jefferson, a rather naive Black Marxist who is happy to do Hinckle's bidding.
Hinckle and his compatriot, Hubert “Safecracker” Gould, track the Book to Abdul, who tells them he no longer has it, as he has sent it to a publisher. They kill him.
PaPa is the one who actually finds the body when he comes to talk to Abdul; he also finds a cryptic note in his hand.
Jes Grew continues to spread, and the Mu’tafikah are actively breaking into museums and taking the works of art that were looted from Africa, Asia, and South America. PaPa LaBas and Black Herman are summoned to a ship docked in the harbor. There they meet a man from Haiti, Benoit Battraville, who tells them what is really happening in Haiti. He also speaks with them for hours about the history of the Atonists trying to stamp out the Work; he advises that PaPa and Black Herman must be on the lookout for a man in the city who is trying to stop Jes Grew by creating a Talking Android.
The intelligence is correct, as Hinckle is desperately trying to put the Android part of the plan into effect. He eventually decides he can use his loyal writer W.W. Jefferson, but they will have to whiten his skin tone first. Jefferson is reluctant and agrees, but they do not get very far before his imposing Reverend father bursts in and interrupts the process, forcibly taking his son away from the hedonistic city and these racist white men.
Hinckle now turns to putting blackface on Gould, preparing for him to attend a notable gala where he can spread the ideas of Jes Grew being derivative and anti-modern to the elite Black crowd.
While all of this is going on, the Hierophant receives a phone call from a powerful tycoon, Walter Mellon. They gloat that Jes Grew has been slowing, but Mellon suggests taking stronger methods. He will initiate an economic panic and thus make it harder for people to afford radios and for musicians to subsist.
At the gala, Gould, tricking the guests in his disguise as a Black poet, begins to utter his offensive verse. He is interrupted by PaPa LaBas and Black Herman, who expose Gould for what he is and announce that Hinckle is guilty. Some of the guests want to know what he is guilty of, as Hinckle has presented himself as a supportive white patron of the Black arts, so PaPa and Black Herman begin a long history of the Work—its origins in Ancient Egypt; its censure by Atonists; its spreading through initiates and the Book of Thoth, which was the written Tet of the music and dancing; the vicissitudes of its power throughout the centuries; and how Jes Grew has come to evolve to its current moment. They tell of Hinckle’s murder of Abdul and how they managed to find the box with the text in it, thanks to the note they deciphered from Abdul.
To PaPa and Black Herman’s chagrin, though, the box that putatively contained Abdul’s manuscript is empty, and PaPa later reads a posthumously postmarked letter from Abdul saying he burnt the Text because it was too lurid.
PaPa and Black Herman are undeterred from their mission of justice, however, and take their two captives to Battraville. Battraville tells them Jes Grew is indeed dissolved for the moment, and he knows why and cannot say, but that the Americans will figure it out for themselves. Jes Grew will never fully die because it is life itself, and there is no end to life.
In an epilogue, we are now in the 1970s; PaPa is 100 years old and still in perfect health. He gives an annual talk on Jes Grew and its history to students, which he delights in. There were many intervening decades in which Jes Grew lay fallow, but now the 1970s is bringing it back again because time is a pendulum, not a river.
