In the book's prologue, the reader meets the narrator, Gunnar Kaufman, a prolific African-American poet whose astronomically successful book, Watermelanin , has sold 126 million copies, elevating him to the status of "Negro Demagogue." The prologue asserts that what follows are Gunnar memoirs, "the battlefield remains of a frightened deserter in the eternal war for civility" (2). The novel opens with a comic survey of Gunnar's family tree, as his mother relates the tales of his family history to him and his sisters. Gunnar in turn regales his classmates with the tales of his ancestors, one of whom Gunnar claims dodged the bullet that eventually killed Crispus Attucks in the Boston Massacre. Gunnar is a young boy growing up in affluent, predominantly white Santa Monica, California with his mother and sisters. His absent father is a sketch artist for the LAPD and rarely sees his children. Gunnar's friends are white, and he spends his free time making enough mischief to gain him mild admonishments from the Santa Monica Shore Patrol.
When Gunnar and his sisters tell their mother they do not want to attend an all-black summer camp because the children there "are different from us," Ms. Kaufman immediately packs up a U-Haul and relocates her family to the West Los Angeles neighborhood of Hillside, a predominantly black community surrounded by a concrete wall that Gunnar describes as the ghetto (37). In Hillside, the Kaufman children encounter an altogether different lifestyle than the one they were accustomed to in Santa Monica. Gunnar learns "the hard way that social norms in Santa Monica were unforgivable breaches of proper Hillside etiquette, and soon after arriving is beaten up by one of the area's local gangs, the "Gun Totin' Hooligans" (52).
Enrolling in the local junior high, Gunnar is offered protection by an administrator who fears that Gunnar's unfamiliarity with Hillside social norms will make him an easy target for harassment. However, Gunnar soon strikes up a friendship with Nicholas Scoby when he is paired with the "thuggish boy" in a reading of William Shakespeare's Othello (66). Scoby is a prodigious basketball player, with a remarkable ability to make, without exception, every basket. Soon after meeting Scoby, Gunnar stuns the local children when he unintentionally exhibits his own, heretofore unknown talent for basketball, dunking the ball into the basket in a pickup game. His talent gains him respect within the Hillside community of youths. Ironically, this unusual talent causes him to stick out enables him to fit into the social scene. Around this time, Gunnar writes his first poem, "Negro Misappropriation of Greek Mythology or, I know Niggers That'll Kick Hercules's Ass" and spray paints the lines across the concrete wall surrounding Hillside. Later, instructed by Scoby, Gunnar changes his hairstyle and attire in an effort to further conform to Hillside society.
As the years pass, Gunnar becomes incredibly popular, both for his talent on the basketball court and for his emerging poetic prowess. However, he remains somewhat of an outcast in his clear lack of dancing talent and his unease with women. His friends, Scoby and feared gang-member and assumed murderer Psycho Loco, dub Gunnar's awkward antics on the dance floor "The White Boy Shuffle." Because of Gunnar's apparent inability to talk to women, Psycho Loco secretly takes it upon himself to order Gunnar a mail order bride from Japan, using a service called "Hot Mamma-Sans of the Orient." Throughout high school, Gunnar continues to write poetry, much of which, we later learn, is published in magazines.
During his sixteenth summer, Gunnar aids in his friends' stealing a department store safe during the turmoil of the 1992 Los Angeles Riots. We learn that Psycho Loco has planned to steal the safe for nine years in retribution for the department store's having moved a race-car set the young Psycho intended to steal on the day he was to steal it. As Gunnar and his friends attempt to load the safe into a car, Gunnar's father and other policemen arrive. Gunnar's father beats him with a nightstick, and Gunnar is hospitalized. When he is released from the hospital, he learns that his friends have been unable to open the safe. Gunnar turns the safe over, finding the combination on the bottom, and opens it. Gunnar refuses to take any of the money, gold, and precious stones inside. In the last two weeks of summer, Gunnar attends a program for the top 100 high school basketball talents in the country, of which Gunnar is number 100. From camp, he sends his friends and family several e-mails, which are documented in the novel. From these e-mails, we learn that both of Gunnar's sisters are pregnant and have moved in with their father. We also learn that Gunnar, despite his basketball talent, is not incredibly interested in the game itself. He is constantly frustrated by his roommates' insistence on constantly talking about the game. Gunnar notes that his roommates even use basketball terms to talk about women.
In return for his father not pressing charges against him and his friends for the safe incident, Gunnar agrees to attend an elite public high school in the San Fernando Valley. Gunnar travels an hour and a half to and from school on a bus. His return to a predominantly white atmosphere is an easy one, and Gunnar notes that he "meshed well" (153). However, he disdains the arrogance of several of the rich, white boys with whom his mother insists he spend time.
In his senior year, Gunnar begins receiving letters from the armed forces academies, Harvard University, and Boston University. He visits a wealthy, African American Harvard graduate in his large home, which overlooks Hillside, realizing that years earlier he and his Holligan friends had stolen a security sign out of the front lawn and destroyed the man's RV. Gunnar is disgusted by the man's superior attitude towards the residents of Hillside and decides he will never attend Harvard. When a recruiter from BU arrives at his house, Gunnar decides to attend BU instead.
Before Gunnar leaves for college, it is revealed that Psycho Loco has indeed ordered Gunnar a wife from Japan when she arrives by UPS on Gunnar's 18th birthday. Yoshiko Katsu speaks little English but is an immediate hit with Gunnar's mother. For their honeymoon, Gunnar and Yoshiko drive to an amusement park, listening to the radio and attempting to bridge the gap between their two mother tongues.
Moving to Boston, Gunnar attends one class at BU: Creative Writing 104. When he tells the class his name, he is overwhelmed by a chorus of accolades as the students in the class recite his now famous poetry back to him and barrage him with questions. Uncomfortable with the attention, Gunnar runs from the room, tearing off his clothes and walking home to his apartment. At the insistence of his professor, who has followed him along with the members of the class, Gunnar agrees to publish a collection of his poetry. The collection will become his book, Watermelanin .
In Boston, Gunnar begins to face a degree of prejudice from other blacks for his marriage to the Japanese Yoshiko. At the insistence of Scoby, who is attending BU, Gunnar attends several meetings of student activist clubs such as the citywide black student union and SWAPO, or the Whities Against Political Obsequeiousness, of which he is the only black member. Waking simultaneously one night from dreams, Gunnar and Yoshiko realize that the latter is pregnant. Gunnar begins traveling on a basketball team with Scoby. He becomes increasingly depressed, and his only consolation are the boxes of Japanese literature sent to him on the road from Yoshiko. In return, Gunnar writes her letters. In these letters, he notes that Scoby "is going insane" (192).
After basketball season ends, Gunnar—now an even greater celebrity—is asked by his publisher to speak at a rally protesting BU's decision to confer an honorary degree upon a corrupt African statesman. Initially unsure of what to say to the crowd, Gunnar eventually tells the crowd that "What we need is some new leaders. Leaders whowon't apostatize like cowards. Some niggers who are ready to die!" (200). The frenzied crowd chants "You! You! You!" and Gunnar's place as "Negro Demagogue" is solidified. From his speech, the media assumes that Gunnar is an advocate of freedom through suicide, and though Gunnar makes it clear thathe means only his own suicide, many across America begin killing themselves and sending their "death poems" to Gunnar. When asked when he plans to commit suicide, Gunnar replies "When I'm good and goddamn ready" (202).
One night, on the beach, a deeply unhappy and depressed Scoby asks Gunnar what the highest building in Boston is before leaving the beach. The next morning Gunnar learns that Scoby has jumped from the roof of the BU law school, killing himself. On the roof, Gunnar finds his friend's suicide note, containing his own death poem.
Gunnar and Yoshiko resolve to return to Hillside, but Gunnar is forced into hiding by an outstanding warrant for his arrest by the LAPD. One night, on the beach with Psycho Loco and Yoshiko, Gunnar walks out into the ocean, realizes he could die if he swam out farther, and gives himself to the currents. Hit with thoughts of his unborn child, he snaps out of a meditative state underwater and swims back to shore. Gunnar and Yoshiko check into a motel, where the spend the remainder of the novel ostensibly hiding from the LAPD, occupying their time by having debates and reading death poems from Gunnar's fans. However, one night, Gunnar walks to 7-Eleven and is caught in a police helicopter's search light. The light follows him home. He and Yoshiko begin taking nighttime walks through Hillside, their way constantly lit by the helicopter. Eventually, they are joined by other members of the community on their walks.
With Gunnar's mother acting as midwife, Yoshiko gives birth to a girl, Naomi Katsu Kaufman, in a small pool in the local park. The birth is attended by a large crowd and is guarded by the members of the Gun Totin' Hooligans. As always, the LAPD helicopter hovers overhead. It drops a box of cigars attached to a parachute when Yoshiko gives birth. In what appears to be Gunnar's father's handwriting, a note is attached that reads, "Congratulations from the Los Angeles Police Department. Maybe this one will grow up with a respect for authority" (219).
As the novel comes to a close, Gunnar begins holding weekly, outdoor open mics, reading his poetry to great crowds. At one gathering, on the two-year anniversary of Scoby's suicide, Gunnar shocks the crowd by chopping off the smallest finger on his right hand with a kitchen knife. His sacrifice "cement[s] his status as savior of the blacks" (223). Elevating Gunnar to the status of cult figure, "spiteful black folks" travel in droves to Hillside, prompting the government to threaten the community with an ultimatum: "rejoin the rest of America or celebrate Kwanza in hell" (224). Hillside residents respond by painting the roofs of the community with white targets. The novel ends with Gunnar, still living in the motel with Yoshiko and Naomi, beginning to tell his daughter the same stories of his family tree told to him in his youth by his mother. The first such tale is that of Gunnar's father. The novel ends with his death poem, left in his LAPD locker before he kills himself by swallowing his own gun.