Here's the trailer for Judd Apatow's "Knocked Up" spin-off, "This Is 40"

Much has transpired since Judd Apatow's 2007 hit Knocked Up. Katherine Heigl adopted two daughters, Seth Rogen tied the knot, Jonah Hill was nominated for an Oscar, and Apatow himself produced over 9,000 movies. And now arrives a trailer for Apatow's fourth studio effort as director, the spin-off (or "sort of sequel") to Knocked Up, This Is 40.

The film follows Heigl's older sister and brother-in-law from the original, Debbie and Pete (played by Apatow regulars Leslie Mann and Paul Rudd), as they confront the aging process and its attendant existential angst. Mann's character is in denial of the big four-oh, and her mid-life crisis prompts a "do better" list designed for the whole family (the kids are played by Mann and Apatow's real-life daughters.) Scored to Fun.'s "We Are Young," the clip, in true Apatovian fashion, encompasses various anatomical hijinks, including a "high nipple" incident involving Melissa McCarthy, Jason Segel's prolific erections, and Rudd's awkward examination of his own taint.

The cast also includes Megan Fox, John Lithgow, Albert Brooks, Chris O'Dowd, Charlyne Yi, and current "It" girl Lena Dunham. Apatow has said that the Pete and Debbie characters are rooted in autobiography, so hopefully his own experiences can inject some fresh humor into the well-worn theme of middle-aged marriage and its discontents. The film doesn't arrive in theaters until December 21, by which time I predict Apatow will have produced at least fifty more movies.