Bright Lights, Bad Karma : I’M LOSING YOU.<i> By Bruce Wagner (Villard: $23, 336 pp.)</i>

This is a heartless novel about a town without pity. The town, of course, is Hollywood, surely the most difficult place on Earth for a writer to capture, if only because the reality of it routinely outstrips invention.

It’s a black hole where conventional human behavior is distorted by the gravity of celebrity, money, power and sex (not necessarily in that order). And that’s not all. Hollywood is now subject to increased--and increasingly aggressive--coverage by the news media.

Celebrities’ comings and goings, unions and dissolutions, rehabs and relapses are chronicled every day on TV and in the tabloids. Even such formerly un-newsworthy folks as studio heads, producers, agents and screenwriters now end up on our breakfast table. The box office rivals box scores; the public knows too much.

Author Bruce Wagner, a veteran screenwriter (“Wild Palms,� “Scenes From the Class Struggle in Beverly Hills�) and Hollywood novelist (“Force Majeure�), has written “I’m Losing You� with an eye toward these realities. In fact, there’s a self-consciousness here that actually works in the book’s favor, because the denizens of Hollywood are nothing if not aware of the cliches and the scrutiny. It’s sort of a shared joke (and a source of secret pride). We work in Hollywood! Isn’t it crazy?

Everything Wagner’s characters say and do has quotes around it. The dialogue is arch and self-referential: “It’s so Hollywood!� Behavior is codified, whether it’s abusing your assistant; engaging in self-destructive, anonymous sex; servicing the stars in some peripheral way, or rebelling against parents who are in the business. (Wagner also gives the players their due. Despite the shallowness of the movies they make and the lifestyles they pursue, they are not idiots. That’s an idea hatched by the snobby East Coast intelligentsia.)

In a bow to Robert Altman’s “The Player,� the cast of characters is vast and in some ways generic. One of them is even referred to as Big Star. Big Star has a shrink and handlers, but we don’t really get to know her because Wagner writes her into a coma before the story is too far along. Elsewhere, a producer is drowned; an assistant hangs himself; a little girl is bludgeoned. Other characters fall from lesser heights: An agent has a breakdown; an actress turns to pornography; a masseuse is thrown in jail. Almost every single relationship, be it straight or gay, is ruined or compromised. Meanwhile, the most repellent character in the book--and that’s saying something--continues to wreak havoc even as those around him are felled by AIDS, cancer and mental disorders.

Wagner also demonstrates--again, accurately--that everybody knows everybody in Hollywood, if several times removed. Thus, Big Star’s agent has an affair with a homeless woman who kidnaps a TV producer’s blind child. The homeless woman’s own child is abused by Big Star and is murdered by an assistant who is sexually abused by a film producer. The film producer is in the midst of developing a project that the agent’s over-the-hill father has been trying to get off the ground for years. The over-the-hill father is having an affair with the mother of Big Star. Got it? And that’s not the half of it.

Fortunately, these byzantine relationships are presented in easily digestible, bite-size pieces. Narrative strategies range from conventional first and third person to e-mail and interrupted cellular phone conversations. (Hence the title: “I’m Losing You.�) Chapter headings ironically echo college courses or colloquia on film (“Women in Film,� “A Guide to the Classics�).

Wagner cannot write a book like this without introducing real-life celebrities. Yet he’s canny about it, skillfully weaving their public personas and the community’s common knowledge into his fictional characters’ lives--another tip of the hat to “The Player.� For example, the Agent and Big Star go to the same shrink as Laura Dern. Rosanna Arquette consoles a director whose dog has been run over. The TV producer and aspiring actress attend one of Carrie Fisher’s preposterously star-studded parties. And so on.

“I’m Losing You� will not suit everyone’s tastes. It’s sure to confirm the belief by many people that Hollywood is a cesspool. To borrow from the hard-boiled prognostications of the Hollywood trades and the studio marketing people, it’ll play on either coast, but it may be too nihilistic for the great American middle. This is not a book about movie-making, but about living and working in Hollywood; it’s a book about people who are lost, because they’ve forgotten why they’re here.