Every literate rocker knows that the Beach Boys' sunny veneer masked a melanoma of family dysfunction metastasizing beneath the skin, dooming the boy genius behind it all. Most writing on them falls into three categories: sanitized official version, hagiographic Brian-boosterism or sleazy exposés. But Oregonian TV critic (and Bill O'Reilly nemesis) Peter Ames Carlin's admirable new book, Catch a Wave (Rodale, $25.95, 342 pages), has an advantage others lack—the 2004 completion of Wilson's infamous, abandoned masterpiece, Smile, gives Carlin's narrative an improbably happy ending tied neatly to its dramatic pivot.

Even the official story admits the Wilson brothers' drug and mental problems, rooted in father Murry's fearsome abuse. But, Carlin reveals, it wasn't just them who felt the wrath of the tribe's elders. When cousin/bandmate Mike Love's parents learned he'd gotten a girl pregnant, his mother—Murry's sister—tossed his possessions out his second-floor window, exiling him from home. Clearly, the warmth of the California sun didn't fully suffuse these households. Brian's tragedy is that while music was his only escape from familial strife, his fate was to make that music in collaboration with that same fucked-up family.

Carlin is a self-avowed fan-as-biographer, yet portrays a Wilson both gifted and flawed, examining the extent to which Wilson may have embraced mental illness as a sort of hall pass to get out of genius class. Frustrating, though, are some niggling factual errors and suspect interpretations of lyrics and studio chatter. Most shockingly, Carlin misquotes Holy Writ—Van Dyke Parks' lyrics to "Cabinessence," derided by Mike Love at the mythic moment of Smile's undoing—rendering the visionary "over and over/ The crow cries uncover the cornfield" as the more pedestrian "the crow flies."

But Carlin lures his interview subjects into colorful candor, as in Parks' reaction to Love's challenge: "It was like I had someone else's job, which was abhorrent to me, because I don't even want my own job." Meanwhile, he finds a defensive Love spinning well-documented events anew: "Just because I said I didn't know what the words meant didn't mean I didn't like them."

And there goes the Wilson-Love clan again—bickering Boys railing against unfair parental judgment. But their terminally arrested development is mirrored in the eternal adolescence their hits evoke, and echoed in the youth-glorifying culture those irresistible paeans to idealized, commercialized childhood helped create. We can't blame them for acting like kids—it's what we love them for and what we've learned from them.