BRIEFLY NOTED.

Half of a Yellow Sun, by Chimamanda Ngozi Adichie (Knopf; $24.95). Based loosely on political events in nineteen-sixties Nigeria, this novel focusses on two wealthy Igbo sisters, Olanna and Kainene, who drift apart as the newly independent nation struggles to remain unified. Olanna falls for an imperious academic whose political convictions mask his personal weaknesses; meanwhile, Kainene becomes involved with a shy, studious British expat. After a series of massacres targeting the Igbo people, the carefully genteel world of the two couples disintegrates. Adichie indicts the outside world for its indifference and probes the arrogance and ignorance that perpetuated the conflict. Yet this is no polemic. The characters and landscape are vividly painted, and details are often used to heartbreaking effect: soldiers, waiting to be armed, clutch sticks carved into the shape of rifles; an Igbo mother, in flight from a massacre, carries her daughter's severed head, the hair lovingly braided.

Chourmo, by Jean-Claude Izzo, translated from the French by Howard Curtis (Europa; $14.95). In the second volume of Izzo's Marseilles trilogy, Fabio Montale, an introspective ex-cop with a placid life based on cronies, aperitifs, and a little fishing, is yanked back into his city's politically charged underworld. On one single sunny day, a beautiful cousin whom he hasn't seen in years enlists his help to find her son, a wayward teen-ager, and an old friend is gunned down in front of him on the street. Izzo, who died in 2000, is more than adept at noir conventions--gritty light, sudden switches of scene, the pervasive rot of cynicism, which sullies even the best intentions. But what makes his work haunting is his extraordinary ability to convey the tastes and smells of Marseilles, and the way memory and obligation dog every step his hero takes.

The Lost, by Daniel Mendelsohn (HarperCollins; $27.95). When Mendelsohn was a ...