The Knocked Up "sort-of sequel" sees Paul Rudd and Leslie Mann reprise their roles as bickering married couple Pete and Debbie, and introduces new additions Megan Fox, Chris O'Dowd, Lena Dunham and Melissa McCarthy.
Taking place a few years after the events of Knocked Up, the film sees Pete and Debbie confronting the realities of ageing.
"It's about getting older," Mann told the LA Times earlier this year. "What the hell happened? Am I making all the right choices? Is this where I'm supposed to be? Is this it?
"All of those dreams that you had when you were young, all of the possibilities, when you lock into marriage and kids, do the possibilities dwindle or go away?"
> Judd Apatow: 'I prefer long comedy films'
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This Is 40 comes out on December 21 in the US, and February 14, 2013 in the UK. Watch the new trailer below: