Offered in a rough chronological order, “Sex: The Revolution” (9 p.m., VH1) will cover four decades of shifting attitudes toward sex and the resulting cultural, social and political tumult, from the 1950s (tonight) to the 1980s on Thursday.

Rich in archival clips and interviews with authors, experts and quip-meisters from John Waters to Bruce Vilanch, “Sex” begins in the late 1940s with the release of the controversial “Kinsey Report,” a scientific tome that quantified the sexual histories of thousands of Americans. It made the shocking argument that premarital sex, adultery, homosexual relations and other unmentionables were a whole lot more common than generally assumed.

Like many documentaries of its kind, “Sex” is both predictable and contradictory. We’re told that America careened from “Ozzie & Harriet” repression to the excesses of “Deep Throat” in the space of two decades and has been freaking out about it ever since. But the 1948 Kinsey study suggests that things may not have been as buttoned down as that picture implies.

If anything, “Sex” is not so much about shifts in sexual behavior but about its depiction in movies, magazines, books, television and the news. As such, a discussion of the end of the Hollywood Code, and the rise of the movie-ratings system, would be helpful.

“Sex” makes much of the political dimensions of its subject. “Revolution” discusses women’s liberation and gay liberation before giving way to the backlash against abortion and pornography of the 1970s and the so-called “culture wars” of more recent decades.

The hot-button politics surrounding the subject still obscures questions of personal inclination. One man’s liberation may be another man’s bad taste. By the early 1980s, even a subversive midnight-movie comedy like “Eating Raoul” could depict suburban hot-tub swingers as oppressive and boring. Do I recoil from “Flavor of Love 3” (7 p.m. and 8 p.m., VH1) because I’m some kind of “conservative” or because I think it’s witless, vulgar and sad?

“Sex” will also air on Sundance next week.

Tonight’s other highlights

¢ At a time when most series are winding down, “American Gladiators” (7 p.m., NBC) enters its second season.

¢ An aspiring music star finds murder on “Bones” (7 p.m., Fox). Former “American Idol” contestants Ace Young and Brandon Rogers guest star.

¢ Competition continues on “Dancing with the Stars” (7 p.m., ABC).

¢ “Celebrity Expose” (7 p.m., MyNetwork) profiles Janet Jackson.

¢ A violent bus accident puts House’s memory on hold on the first of a two-part season finale of “House” (8 p.m., Fox).

¢ “American Experience” (8 p.m., PBS, check local listings) continues its series of presidential biographies with part 1 of a 1994 profile of Franklin Roosevelt.

¢ Barbara Walters appears on “Larry King Live” (8 p.m., CNN).

¢ Allison suffers nightmares about a couple’s “dream house” while Joe pursues a business venture on the season finale of “Medium” (9 p.m., NBC).

¢ A proposal is made as the season ends on “The Bachelor” (9 p.m., ABC).