It’s a thin line, Chrissie Hynde sang, between love and hate. Reading Lawrence Osborne’s new novel, “The Forgiven,” you may sometimes feel that you are straddling that line in a vertiginous way, like Philippe Petit walking a high wire between the World Trade Center towers.  I scuttled safely across to the love side. Mr. Osborne’s second novel is a sinister and streamlined entertainment in the tradition of Paul Bowles, Evelyn Waugh and the early Ian McEwan. It’s about a wealthy British couple who, on their way to a lavish weekend party in the Moroccan desert, accidentally run over and kill a young man who is apparently, late at night, trying to sell fossils by the roadside. They put his body in their car and, to their host’s horror, take it along. The police arrive. So does, soon enough, the victim’s impoverished father.  “Everything happens at parties,” Jane Austen said. At this weekend-long debauch, thrown by Richard and Dally, a worldly gay couple, for their international set of friends, some of whom arrive in helicopters, everything happens amid opulence and quirk. There are fireworks and outdoor discos and fake silver palm trees; precious food flown in from across the planet; local boys in pirate dress; “succulent” French girls; figs and white orchids; free refills on cocaine; “glissando female laughter”; fire eaters and local honey seasoned with cannabis. A photographer from the Styles section of The New York Times is there to chronicle and consecrate it all. It’s an haute mess, and a wicked feast for the eyes of the enraged local people, who imagine infidel “orgies with Jaguars waiting outside.” (They are not far off.)  The shimmer of these events, contrasted with the bleak lives of poor Moroccans, allows Mr. Osborne to tinker with his novel’s fatalistic themes: the clash of worlds, post-colonial angst, the cultural misunderstandings that have grown only more profound since Sept. 11.  The over-the-top spectacle of this party can also, however, stand in for a few of the bummers about “The Forgiven.” Mr. Osborne places his thumb too heavily on certain scales. There are flecks of awkward dialogue. Too often he tells rather than shows.  You will be willing to forgive “The Forgiven” almost anything, however, because of how quickly this book moves, and how fluent and hardheaded a writer the author is. Mr. Osborne, who is British and a seasoned travel journalist, has written books about Paris and Bangkok, among other places. He’s written a book about wine (“The Accidental Connoisseur”) and a previous novel, “Ania Malina” (1986). Any of these will see you happily through a long weekend in front of fall’s first indoor fire.  In “The Forgiven” he has upped his narrative game. This is a lean book that moves like a panther. Even better, Mr. Osborne has a keen and sometimes cruel eye for humans and their manners and morals, and for the natural world. You can open to almost any page and find brutally fine observations.  A lizard has eyes with “pieces of dark orange rind in them”; tall flowering weeds are “pestered by bees.” Here is how he sizes up a stoned couple at the party: “Their faces were like young wolves. The girl looked like Isadora Duncan just before the strangulation.”  He deposes about etiquette: “A red wine is held by the neck, a woman by the waist, and a bottle of champagne by the derrière.” On Morocco’s streets “people sat on mats, staring at the traffic like people who are expecting a downfall of volcanic ash that will bury them for centuries.” This is the sound of a writer whose pilot light is always left on.  The book’s most vivid character is its most hateful one. This would be David, a curmudgeonly British doctor — to judge by the author’s descriptions, he physically resembles the late art critic Robert Hughes — who is drunk behind the wheel when he runs over the young man. He finds most Moroccans primitive and irrational; he calls them “towel-heads.” About rural Morocco, he thinks: “It was a zone of barbarism, of prehistory. It was a desolate comedy with child labor.”  To Mr. Osborne’s credit, David does not sink entirely into caricature. This book has complicated subsets of sympathies that extend even to him. One of the author’s real achievements is how many heads he manages to climb into. There are sensitive portraits of both men and women, visitors and Moroccans. There are chapters that investigate the interior life of the young man who is killed. About Moroccans, Mr. Osborne observes, “They were born observers and critics, because that’s the way history had made them.”  “The Forgiven” is also a spindly portrait of a failing marriage. About David’s younger wife, a children’s book author named Jo, we read toward the end of the book, “In 48 hours she had been completely destroyed from top to bottom, but at the same time liberated and rebuilt.”  The ending of “The Forgiven” is surprising and dark and excellent, and I don’t wish to give even a hint of it away. Suffice it to say that Mr. Osborne finds deep meaning, and deep overlapping ironies, in various concepts of punishment and forgiveness.  His elegant book seems like a ruthless and skeptical analysis of something Paul Bowles wrote in “The Sheltering Sky,” his famous novel about Morocco. “Whoever invented the concept of fairness, anyway?” Mr. Bowles’s narrator asked. “Isn’t everything easier if you simply get rid of the idea of justice altogether? You think the quantity of pleasure, the degree of suffering is constant among all men?”  He added, “If it comes out even, it’s only because the final sum is zero.”
âThe Forgivenâ explores a clash of worlds between Moroccans and Western visitors who converge at a weekend-long bacchanal in a desert villa.