When a one-night stand that should have ended with the sunrise has unexpectedly permanent consequences, the reluctant odd couple attempts to transform their tentative relationship into a lasting love in a conception comedy from the people who brought viewers The 40-Year-Old Virgin. Twenty-four-year-old entertainment journalist Allison Scott (Katherine Heigl) was on the fast track to the big time when an alcohol-fueled one-night stand with responsibility-shirking slacker Ben Stone (Seth Rogen) found her professional priorities taking a back seat to the prospect of parenthood. Now, as overgrown kid Ben is faced with the choice of maintaining his carefree lifestyle or assuming the responsibilities of fatherhood, his decision to stick around is only the beginning of the unlikely couple's nine-month courtship. In order to make things work between the pair, however, there's going to have to be some compromise, and when Allison and Ben decide to take a shot at love, they quickly find that building a relationship from scratch isn't nearly as easy as making a baby.