One trouble with Joe McGinniss's true-crime anatomy, Fatal Vision …, is that it's 663 pages long. If the prose is a little wooden and the insights less than electric, that's like forever. This isn't the Rosenberg case. The book's great length testifies to the author's earnestness, as well as (perhaps) to commercial savvy; but it's insensitive to the enjoyment of true-crime.

Another trouble is that the central mystery of the book, the engine of suspense, is resolved early on—indeed, for reviewers, before the book even begins, in the publicity rap. The suspense is not whether Jeffrey MacDonald, back in 1970, actually bludgeoned, knifed, and ice-picked his pregnant wife and two little daughters ages five and two to death, but whether McGinniss thinks he did. There's a suggestion that McGinniss had doubts at first. But now he's convinced. As was a jury in 1979. Which leaves us with the details. One scrabbles...