By his own estimation, Jude Keffy-Horn, the skateboarding teen drug abuser turned clean-living proselytizer in Eleanor Henderson’s first novel, “Ten Thousand Saints,” is an “inessential” character. He’s the one standing outside the bathroom while his friend Teddy is inside impregnating Eliza, a coke-snorting trust-fund girl. Though Teddy dies after he and Jude huff turpentine and Freon on a winter night during the novel’s first chapter, Jude manages to survive. Later, he stands by again to witness Teddy’s half-brother Johnny, a punk rocker, Hare Krishna devotee and straight edge pioneer nicknamed “Mr. Clean,” marry the pregnant Eliza — never mind that Jude is the one who actually loves her. “He was the tissue that bound the essential members together,” Henderson writes of Jude. But he “was joined to no one.”

Great American literature is chock-full of seemingly “inessential characters” like Jude, with Nick Carraways standing in the shadows cast by Jay Gatsbys; Sal Paradises and Patti Smiths subsuming their personalities to cooler-than-life Dean Moriartys and Robert Mapplethorpes. But in Henderson’s empathetic novel of wayward youth and their wayward parents, little seems to separate Jude from the characters he encounters on his journey toward becoming a responsible adult; all seem equally flawed, equally heroic, equally selfish, equally essential or inessential, depending on your point of view.

Their romances and battles play out during the twilight of the Reagan 1980s, near the end of the sketchy New York of Ed Koch’s reign, but not quite in the gentrified Manhattan that became the hallmark of Giuliani Time. Henderson’s novel pays tribute to this transitional period and the seemingly marginal people who inhabited it. Hers is a book where minor characters play the major roles.

The author follows Jude back and forth between his fairly bleak home town of Lintonburg, Vt. (Lintonburg is an anagram for Bur­lington) and the Lower East Side of Manhattan as Jude forms a loose collective that is equal parts punk band and street gang. Henderson proves herself to be an expert ethnographer; her detail work is phenomenal. A scene in which Jude joins a game of laser tag in the subway system is particularly well-
realized and almost demands to be filmed. Henderson’s witty, offhand observations and throwaway lines are worthy of Jonathan Richman and the Modern Lovers, whose song “I’m Straight” could be seen as this novel’s anthem. One character sleeps in a bathroom, “curled around the toilet like a cashew”; the baby grand piano in Eliza’s mother’s apartment is “posed like an open-jawed shark.”

But her characterizations demonstrate Henderson’s greatest skill. Even the ones who receive comparatively little stage time are always precisely defined: Jude’s estranged dad, Les, deals drugs on the LES (Lower East Side) and doesn’t mind his kid smoking reefer as long as it’s his reefer; Jude’s glass-blowing mom does a good business in bongs in Vermont; the dorky teens join Jude’s straight edge scene as a way of legitimizing their social awkwardness. “They were scared of girls, anyway,” Henderson writes of these lads, defining their self-image as “I’m not ugly, I’m straight edge.” Not all of these characters are particularly appealing, but they’re memorable, and Henderson’s affection for them is palpable.

‘’Ten Thousand Saints: A Novel’’ by Eleanor Henderson, who will be at Politics and Prose bookstore Monday at 7 p.m. (Ecco)

Whether readers will share the author’s sympathies for her vividly realized characters, however, is debatable. Their interactions could have benefited from a bit more of the historical and political context that was employed to excellent effect by Jennifer Gilmore in “Something Red” or from more of the ironic distance seen in Jo Ann Beard’s “In Zanesville,” two fine recent novels that cover some similar ground. At times, the experience of reading about Jude and Henderson’s other “saints” recalls that of meeting a close friend’s significant other who doesn’t quite live up to the billing. After Jude rips off an admittedly annoying drug dealer and later savagely beats him up, it’s tough to take much interest in whether Jude will eventually achieve some form of redemption. Ditto for Johnny and for Eliza, too, whose decision about who will parent her baby seems to have little to do with the good of the child.

Indeed, for the reader who spent any time in or around the Lower East Side in the late 1980s, “Ten Thousand Saints” may provoke more ambivalence than nostalgia. Nice place to visit, this Manhattan, but you might feel glad you don’t live there. In the novel’s brief, almost perfunctory coda set in 2006, Jude seems relieved that he survived and has moved on. When the now 30-something Jude walks through his gentrified old neighborhood, the experience evokes a brief longing for what he will never recapture. But Jude’s life is elsewhere now, and this yearning passes quickly. This world is no longer essential, not even to him.

Langer’s most recent novel is “The Thieves of Manhattan.” He divides his time between New York City and Bloomington, Ind.

Eleanor Henderson will be at Politics and Prose bookstore Monday at 7 p.m.

TEN THOUSAND SAINTS

By Eleanor Henderson

Ecco. 388 pp. $26.99