Junot Díaz’s first book, “Drown” (1996), a collection of stories, did everything right. It balanced an unsung dialect — Dominican slang — against a personal voice; it told stories that oscillated smoothly between detail and symbolism, offering a violent incident before modulating, without apparent haste, toward a firm, quiet conclusion. In the title story, memories of night-time swimming at the neighborhood pool contextualize the submerged ego of a juvenile delinquent and frame an episode of undiscussable sexual experimentation. The story ends with a portrait of unexplained symbiosis between the narrator and his habitually silent mother. The stories were textbook accomplishments: they taught the reader something about writerly restraint, but also something about license, all shown to be possible within the confines of literary convention.

After 10 years, Mr. Díaz has published a second book, a novel, called “The Brief Wondrous Life of Oscar Wao” (Riverhead Books, 340 pages, $24.95). As the trendy title suggests, literary culture has not stood still since 1996. Mr. Díaz’s second book recalls some of the biggest names to have been made since his own debut. The quirky pluck of Mr. Díaz’s Oscar, a sci-fi Dungeons & Dragons supernerd, would not be out of place in a novel by Gary Shteyngart. Yunior, his best friend and the book’s narrator, employs an earnestly exaggerative voice comparable to Dave Egger’s older-brother narration. Most interesting, the farouche portrayal of multiculturalism in “Drown” has given way to a more expository approach, one that delights in the specificity of its swagger. “Oscar Wao” follows the model of Zadie Smith, who outlined a sunnier, pop appeal for ethnic mash-ups in “White Teeth.”

Yunior, who appeared in many of the stories in “Drown” and seems to stand in for the author, has a special way of speaking. As Oscar’s roommate at Rutgers, he represents the college Lothario, articulate but insistently street. Additionally, he shares some of Oscar’s nerdy, otaku knowledge: “Perhaps if like me he’d been able to hide his otakuness maybe s— would have been easier for him, but he couldn’t. Dude wore his nerdiness like a Jedi wore his lightsaber.”

The novel’s main plot revolves around Oscar’s obesity and his desperate virginity. Yunior hates to see a fellow Dominican failing with women: “Dude was supposed to have Atomic Level G.” This could be the setup to a comic novel, but Mr. Díaz endows Oscar with transcendent crushes, ones that resemble the show-stopping power surges of his anime heroes. Oscar gets his heart broken routinely, and he therefore considers his amor to be “this huge sputtering force,” rather like an comic character’s tragic-heroic death ray.

At another level, the novel is all about an ancient Dominican curse; a “fukú.” The first fukú arrived with Columbus, or it may have come from Africa — it stands in for all that is terrible in the island’s destiny. If nerd culture is this novel’s texture, its well-researched payload of detail, fukú is its Icenine, its Jedi force, its conspiracy theory. It replaces moral free will with apocalyptic meaningfulness. Yunior sells fukú hard, and indeed, it dovetails with Oscar’s brand of enthusiasm: The fukú is “like Darkseid’s Omega Effect, like Morgoth’s bane, no matter how many turns and digressions this shit might take, it always — and I mean always gets its man.” Yunior often sounds like he’s trying to impress a younger cousin.

The curse isn’t just a local concern for his characters, however, and Mr. Díaz links the fukú with the Dominican dictator, Rafael Leonidas Trujillo Molina, providing 33 historical footnotes “for those of you who missed your mandatory two seconds of Dominican history.” Oscar’s bad luck with girls may, according to Yunior, devolve from the dictator’s evil. These footnotes make up some of the most entertaining material in the novel; they divert the novel’s pumped-up, epic emotionalism toward the truly sweeping story of Dominican history.

The same epic style feels forced when applied to Oscar and his family. We learn, in discontinuous sections dating between 1944 and 1995, of Oscar’s mother’s and sister’s run-ins with Trujillo and his thugs, all fated by an original dispute between his grandfather and the dictator. Yunior wants to dazzle us with destiny; he looks through the family’s history for proof of its magic. Accordingly, he often sounds as if he is scrolling through the story, rather than writing it. When Oscar’s mother, Belicia, goes to her first nightclub, he writes: “Here at last is her smile: burn it into your memory; you won’t see it often.” The smile isn’t described, its talismanic importance is simply asserted. The man she meets there turns out to be Trujillo’s brother-in-law, and he leads Belicia toward ruin. She is badly beaten, and although here Mr. Díaz supplies specifics — “her clavicle, chicken-boned; her right humerus, a triple fracture … About 167 points of damage in total” — he concludes the scene by reaching for the belabored fanfare that weakens so many passages in the book: “All that can be said is that it was the end of language, the end of hope. It was the sort of beating that breaks people, breaks them utterly.”

In “Drown,” Mr. Diaz mastered a restrained style that took tragedy at face value, without needing to invent a world-historical curse. With the mock-heroic “Oscar Wao,” Mr. Díaz has written a kind of satire of an ethnic subculture — one that believes its native fukú killed Kennedy, for example — with nerd enthusiasm as a totally unexpected metaphor for same. But the novel isn’t leavened like a satire; its boastfulness is too insistent. Mr. Díaz remains an excellent writer, and a particular master of voice: the Afro-Dominican nerd-speak that he delivers here never loses its quiver.

blytal@nysun.com