Thou Shalt Kill

In 1984 an unemployeD 42-year-old construction worker named Ron Lafferty received a message from God instructing him to kill his brother's wife Brenda and her 15-month-old baby Erica. Four months later, Ron — with the help of another brother, Dan — carried out his divine assignment with a 10-in. boning knife. Jon Krakauer tells the story of the Lafferty brothers in Under the Banner of Heaven (Doubleday; 372 pages).

True crime isn't really Krakauer's beat — he's the author of Into Thin Air, the bestselling account of a disastrous Everest expedition — but he takes an able, earnest stab at it. It turns out that Ron and Dan weren't just plain crazy. They were members of a fundamentalist Mormon sect, and Krakauer spends much of the book putting their crime in the context of the strange and violent history of the Mormon Church.

Like a lot of popular nonfiction, Heaven belongs to the school of the lurid glimpse, giving readers an anthropological peep at a genuine subculture. But Krakauer never succeeds in getting inside his villains' heads — they're just a pair of holy robots obeying the evil software of their deity — and his main theme, that "there is a dark side to religious devotion," isn't exactly breaking news in 2003. If nothing else, the book is a bracing reminder that Americans aren't special. We're as capable of breeding violent religious fanatics as anybody else.