It begins with a woman. She opens the screen door to a small home on a small farm in the middle of America's heartland, takes a deep breath of wholesome prairie air, grabs an old-fashioned butter churn, and gets to work. Her hands firmly grasp the handle, and her arms methodically pump up and down in a steady rhythm, faster and faster, whipping the frothy, sticky cream to a viscous consistency.I'm expecting John Dough or Ron Jeremy to amble out of the corn at any minute and coyly introduce himself. Instead, Curly the cowboy shows up, singing that chestnut of American theater, “Oh, What a Beautiful Mornin'.” It isn't enough to shake the sexual tension. In fact, it escalates it. This song, which I had for years viewed as an American secular hymn, is revealed to be a lovesick paean to the herd of cattle Curly just passed: “And a little brown maverick is winking her eye.”I may be a pervert, but so help me Larry Flynt, based on the superlative production of Oklahoma! playing at the Huntington Beach Playhouse, Oscar Hammerstein II and Richard Rodgers must have had a streak of blue in them as well. How else do you explain the sexual metaphors, situations, wisecracks, songs, allusions and tone of Oklahoma!? From the opening image to the last-an oversexed, milk-fed prairie beauty dusting hay from her skirt after a quick tryst in the barn with her boyfriend-Oklahoma! is soft porn at its squishiest.Director Kent Johnson's sexual interpretation-planned or not-only makes sense, given sex's pre-eminent place on America's collective obsession meter. It's natural that Oklahoma!, the first modern musical and perhaps the Great American Musical, is positively soaked in sex-and sex's supporting players, love and romance.For those who came in late, Oklahoma! is set just after the turn of the century, when the future state was still a territory and cowboys bickered with homesteaders over where the West should go. Curly (Scott Ruiz) is Stetson over spurs for Laurey (Bree Long), the beautiful niece of the play's matriarch, Aunt Eller (a too youthful Laurie Hancock, who doesn't have nearly enough piss or vinegar). But dastardly ranch hand Judd Fry (Ron Samson), who's papered his walls with French porn, also covets Laurey. Confused and afraid of commitment, Laurey plays the men off each other-to rather tragic consequences. The central story is buttressed by numerous subplots, most notably those involving Ado Annie (an excellent Natalia Schroeder) and her two suitors: Ali Hakim (a very funny Daryl Mendelson), a lascivious Persian peddler, and Will (Michael De Mocko), a homespun kid fresh off his big trip to cosmopolitan Kansas City.Because Oklahoma! is produced so often and so poorly (and because it features two of the most annoyingly dopey songs in American pop music-the title track and “Oh, What a Beautiful Mornin'”), it's easy to forget it was a groundbreaking musical. Other shows had integrated song and story, but Oklahoma! did it better than any show to date and introduced a third element: dance. In Oklahoma!, the choreography amplifies characters and situations while advancing the story-for example, the use of ballet in Laurey's nightmare sequence, which artfully articulates her fear of committing to Curly.That doesn't mean Oklahoma! doesn't suffer from the corn-fed wholesomeness and sappiness that plague many musicals. This production, good as it is, can't do anything about that. But it does brilliantly illustrate the sexual undercurrents of Oklahoma!-undercurrents that are utterly submerged in most stagings-without making us feel that Johnson and the cast are trying to sex up the show. It happens naturally and effortlessly, showing that, at its best, community theater is the purest, most honest form. Where professional and semiprofessional theater have money, careers and prestige at stake, community theater is usually composed of people doing it for love, older actors who just enjoy the stage, and younger actors starting out. It's the last group that makes this version of Oklahoma! work so well. Before directors, agents, fellow actors and your own enormously misguided ego sink their hooks into you, you're raw material. You can only bring what you know onto the stage. And if there's one thing young people can relate to, it's sexuality, what with raging hormones and all that.And that's what makes this Oklahoma! the naughtiest, most entertaining version of the play I've seen. It feels oddly real, not lost in overblown, sappy sentiment or the dreary haze of nostalgia that's crippled everything from the 1955 film to the 1979 Broadway revival and cast album.Several performances deserve special mention. Ruiz's Curly is excellent, and he anchors the show. He possesses a strong, expressive voice, which he uses to color each of his songs distinctively. In his larynx, the song “Surrey With the Fringe on Top” is an effective love song despite bearing only a trace of romance in the lyrics. He also lends a charismatic presence onstage, making the often absurd character of Curly (a tough-as-nails cowpoke who bursts into ballads at the drop of a lariat) quite believable.Long's Laurey is also excellent-when she's not singing. Her voice is too good for the part, one of those highly trained, operatic, keening types that drive me nuts in the theater. But her portrayal of Laurey painfully captures the anxiety of a young woman on the threshold of maturity.However, the real standout-and the best illustration of the sex oozing from this production-is Schroeder's Ado Annie. As the girl who just can't say no to male advances, Annie's overheated carnality is usually played in a cutesy, wink-wink-nudge-nudge way. But Schroeder, close to the age of the teenage character, plays her absolutely straight: she just can't wait to get laid. Of course, she settles on the logical, safe choice. But she still radiates sexuality-and never in a slutty, dirty or obscene way. It's perfectly natural, perfectly human. In short, it's perfectly American.Oklahoma! at the Huntington Beach Playhouse, 7111 Talbert Ave., Huntington Beach, (714) 375-0696. Thurs.-Sat., 8 p.m.; Sun., 2 p.m. Through Sept. 13. $13-$16; students with IDs get in for $5 on Thursdays.