By Glen Hirshberg

Carroll & Graf. 324 pp. $24

When 28-year-old Mattie makes a pilgrimage back to his home town of Detroit, he's pretty much of a mess. It's winter in the Motor City, and Mattie seems already to be in the winter of his life. His marriage is on the rocks, his relationship with his parents and brother is troubled, his career as a fine artist is washed up. Worse than any of these separate things is that all joy has been leached away from him; he's been battling severe unhappiness for so long and for such good reason that (perhaps, just perhaps) there's no viable future at all left for him. This trip, back to the scene of his traumatized childhood, may be a literal last chance. Poor Detroit has seen better days as well. It's in wretched condition, piled high with "filthy snow," littered with the wreckage of dead cars. Moral and physical failure manifests at every turn.

Mattie begins to call up some of his old grammar school friends -- he was only 11 when he left town, under mysterious circumstances -- and is greeted with guarded surprise. His stated purpose is to check out two of his old, dear friends: Spencer, one of the first African American kids to attend Mattie's school, and Theresa Daughrety, a girl who lived down the street from Mattie, rigorously trained by her father to become a child genius. And, of course, Mattie needs to find himself.

The story switches from the year 1996, when the adult Mattie returns to his home town, back to 1976, '77, '78, as the sweetness of childhood played itself out for these three kids. Their lives in the sixth and seventh grade are punctuated by a devilish parlor game set up by Theresa's dad to validate his definition of her as a prodigy: "Mind War," a variation of Trivial Pursuit with very untrivial topics. But there are other games as well, among them something called "Side Car," in which Mattie and Spence unite to become a physical battering ram for their classmates.

This technically perfect, beautifully rendered childhood is what makes "The Snowman's Children" so powerful. Mattie's parents, really just kids themselves, are perfectly believable, and his popular younger brother could step off the page and right into our living rooms. This is "normal" American suburban life seen without cliches, a series of houses on a series of streets, where a series of parents try -- or don't try -- to make life safe for their kids. That safety should extend to everyone, even the geekiest (because no questions about it, Mattie, Spence and Theresa all have a high outcast quotient; they hang together because they're all weird).

Then the unspeakable happens. A child-killer turns up in Detroit, murdering a string of kids their age. (As if life weren't hard enough.) Parents are supposed to protect their children, but how do you protect against a serial killer? The adults here are only human, locked in private worlds of their own. Theresa's crazy widowed father still wants to have the smartest daughter known to man. (Meanwhile, he starts an affair with the babysitter.) Spence's mother, a white woman married to a black guy, is in the process of being left by her husband and ostracized by his family. Mattie's folks, the strongest of the lot, can barely keep their heads above water.

Meanwhile, Theresa is going absolutely, literally mad. Everybody sees it (except, perhaps, for that wacky single-minded dad of hers), but no one can seem to do anything about it.

That's in the fictional present time; the adult Mattie seeks out the adult Spence, a minister now in an African American evangelical church. Spence enigmatically greets Mattie as the "devil" and steadfastly denies knowing anything at all about Theresa.

That's about one-third of the plot. The theme here is that there's enough evil in this world to go around for everyone. Maybe these little kids aren't as innocent as they seem to be. Maybe one or more of them is doomed. Maybe evil has to do with the world falling apart. And once it's fallen -- even in one person's eyes -- there's hell to pay, putting it back together again.

Glen Hirshberg has been nominated for the 2001 International Horror Award, and I'm sure I won't be the only one to suggest that "The Snowman's Children" is a hybrid of two genres -- the first, a careful social realism; the second, a free-for-all Gothic-horror jamboree. But in the long run, who cares? Bonehead editors have been instructing writers for years that it's absolutely awful if their work "falls between two stools." But there's evidence that a lot of interesting stuff happens when you fall off one stool or another. In the great cosmic barroom of life, most of the action happens in free fall, heading toward the floor, or maybe breaking through into another, better reality.