How is it possible that both ``Deep Throats'' are back in the news at the same time, if for different reasons? Not long after the 1972 release of ``Deep Throat'', www.xxxdeepthroat.com and President Richard Nixon's attempt to have it criminalized, Washington Post reporters Bob Woodward and Carl Bernstein, whose work on the Watergate break-in brought down the Nixon White House, dubbed an anonymous source ``Deep Throat.'' (This Deep Throat, whose identity is still unknown, is reportedly gravely ill.) The expression ``deep throat,'' of course, is a reference to a sex act made famous by that notorious XXX-rated film of the same name, a $25,000, perhaps mob-backed movie that inflamed conservatives everywhere and has gone on to become the most profitable film ever made, with more than $600 million in grosses to date. (The original film is reportedly being re-released shortly in edited form for a new generation.) ``Deep Throat'' is also the subject of Fenton Bailey and Randy Barbato's provocatively titled ``Inside Deep Throat,'' an NC-17-rated documentary about the XXX-rated film that took America by storm. Comprising vintage news footage, archival interviews, interviews with survivors involved in the film, such observers of the so-called Sexual Revolution as Dick Cavett and Hugh Hefner, and, yes, footage from ``Deep Throat'' itself, ``Inside Deep Throat'' is an accomplished, if often slow piece of work and a serious examination of American culture and censorship. For better or worse, ``Deep Throat'' provided a serious test of the Constitution's First Amendment. It also made headlines in Variety, the film industry's bible, in large part because it challenged mainstream fare at the box office. A pop culture phenomenon, ``Deep Throat'' was invoked on such iconic TV programs as ``Rowan & Martin's Laugh-In'' and ``Sanford and Son'' and became a punch line in Johnny Carson routines. Linda Lovelace and Harry Reems, the stars of the film, were given an opportunity to parlay their notoriety into legitimate stardom, although neither succeeded. Lovelace, who converted to feminism and condemned the XXX-rated film industry in her memoir ``Ordeal,'' died in a traffic accident in 2002. Reems, looking fit, but more subdued and grayer, works as a real estate agent in Utah. ``Deep Throat'' director Gerard Damiano, who toyed with calling the film ``The Sword Swallower,'' is now an ordinary if garishly dressed Florida retiree. Bailey and Barbato (``The Eyes of Tammy Faye'') have rounded up an impressive, at times hilarious group of commentators and social gadflies - Helen Gurley Brown, Larry Flynt, Alan Dershowitz, Dr. Ruth Westheimer, John Waters, Erica Jong, Norman Mailer, whose remarks are particularly trenchant, a scowling Gore Vidal and ever ebullient Camille Paglia. Dennis Hopper narrates. Mainstream filmmaker Wes Craven (``Nightmare on Elm Street'') admits he got his start in porn, like many others. In a jaw-dropping remark, the aforementioned, eternal ``Cosmo''-girl Brown sings the praises of male ejaculate as a moisturizer. As this lineup suggests, ``Inside Deep Throat,'' which was produced by Ron Howard's longtime producer Brian Grazer, is a serious look at what Paglia calls an ``epochal moment'' in American cultural history. Wherever you stand on the issue of XXX-rated films, you may find something of value here. The first NC-17 picture released by Universal Pictures since ``Henry & June'' (1990), ``Inside Deep Throat'' is itself a kind of test as well, and a caveat is probably also in order. Some might question the wisdom, not to mention the morality, of showing a graphic sex scene in a film playing in a local theater. But after all, this is called ``Inside Deep Throat,'' and not including the act that gives the film and its subject their names might have been a major omission.