Janet Reitman's Inside Scientology isn't the sleazy Scientology tell-all you've been hoping for. It's not weighted down with celebrity smarm or baseless suppositions about L. Ron Hubbard's personal life. And maybe that's a shame. I'd love to read that kind of a book. But this book is way more valuable than that: It's a fastidiously reported history of what the cover calls "America's Most Secretive Religion."

That does mean that Inside Scientology can be, at times, a little boring. Reitman is telling the comprehensive story of the building of a religion, and that includes a whole lot of modern version of begats and begots, mostly taking the form here of real estate transactions and other business dealings. But those dry stretches are totally worth it for the passages that deflate Scientology doctrine about L. Ron Hubbard's career (he was kind of a lofty ponce) and Tom Cruise's career as a Scientologist (when he discovered the truth about Xenu and the other secrets behind Scientology, someone reports that Cruise "freaked out and was like, What the fuck is this science fiction shit?") and the horrific story of a mentally ill woman who died in church custody. It's not easy reading—the latter story is heartbreaking—but it's informative, factually solid, and brave.

If you're planning one last summer vacation, Inside Scientology might not be the book you've been dreaming of—it's not lurid, after all, and it's kind of a downer in parts—but you'd come back from your vacation a little more informed about the interior of a society that doesn't want you know about its interiors, and you'd have supported a powerful work of journalism. What else do you really want out of a book?