Adult-skewing fare should continue to reign in the domestic B.O.’s first fall frame: With a projected launch north of $20 million, Warner Bros. ensembler “Contagion” looks set to wage germ warfare on three-week B.O. champ “The Help.”

“Contagion,” from Participant Media and Imagenation Abu Dhabi, bows alongside a pair of pics targeted at those under 25: “Warrior” and “Bucky Larson: Born to Be a Star.”

Late August and post-Labor Day box office is typically driven by adult fodder (e.g., 2010’s “Red” and “The Town”) and an influx of specialty titles. This weekend, indies bowing include Anchor Bay’s Rooney Mara starrer “Tanner Hall” and IFC’s Brit period laffer “Burke and Hare.”

Monster movie “Creature,” self-distributed by Sid and Jon Sheinberg’s Bubble Releasing, also opens wide at 1,507 locations.Overseas, Sony’s “The Smurfs” could win again (cume is nearing $300 million), though titles including “Rise of the Planet of the Apes” ($189 million) and “Final Destination 5” ($61 million) continue to make headway internationally. “Contagion” bows day-and-date in Italy and smaller Asian markets.

It’s not surprising to see high-profile pics like “Contagion” bow after Labor Day weekend — historically one of the slowest weekends at the box office. Because of that stigma, some distribs avoid the Labor Day frame so as not to discourage filmmakers or studio execs.

But the first weekend following Labor Day typically isn’t that busy, either.

The upside is that while kids are busy settling into school, over-25 moviegoers are more active at multiplexes and hungry for mature fare following the box office’s blockbuster season. Think of “The Help,” which has grossed $127 million domestically.

“Contagion,” helmed by Steven Soderbergh, sports a topnotch cast including Matt Damon, Gwyneth Paltrow, Kate Winslet, Jude Law and Marion Cotillard. The thriller premiered at the Venice Film Festival and has racked up largely positive reviews.

Lionsgate said it hopes “Warrior,” starring Tom Hardy and Joel Edgerton, will broaden to adult auds, based on positive word of mouth. Pic, which opens at 1,869 engagements, should play best (at first) to core younger males, driving a projected opening of $6 million-$8 million.

The success of “Warrior,” budgeted at a reported mid-$20 millions, will hinge on the extent of the popularity of mixed martial arts. Lionsgate decided to sneak the pic last weekend, with additional advance word of mouth screenings to segments including faith-based auds.

Meanwhile, Sony’s “Bucky Larson: Born to Be a Star” should figure low in overall weekend standing, with an estimated launch at around $4 million. Luckily for Sony, the Nick Swardson laffer, about a Midwesterner who moves to Hollywood to become a porn star, cost less than $10 million to produce.

Sony mainstay Adam Sandler co-wrote the script with Swardson and Allen Covert. Sandler produced through his Happy Madison banner.

A pair of foreign specialty pics also bow this weekend in the U.S.: Bollywood film “My Brother’s Bride,” being distribbed by Yah Raj Films, opens at 75 engagements, while China Lion’s “Love in Space,” which Fox Intl. bows today in China, launches at 15 Stateside engagements.