Holly's (Katherine Heigl) best friend Alison (Christina Hendricks) has set her up on a blind date with Eric Messer (Josh Duhamel), whose long-time buddy Peter (Hayes MacArthur) is Alison's husband. Sounds like a good match and Holly is excited. But Eric shows up an hour late, wants her to ride on his motorcycle in her glamorous dress, and has not made a reservation for dinner as promised. These three strikes are enough to count him out but the fourth surprise seals the separation: he takes a call on his cell phone and sets up a sex date for later in the evening. Holly can't recall a worse date and returns to her job — running a small but popular boutique café. Meanwhile, Messer (he goes by his last name) continues bedding women and dreaming about leaping from broadcast technician to a job as director of national sports television.

Holly and Messer meet again at Peter and Alison's, remembering full well how much they loathe each other. She sees him as a chauvinist pig and he sees her as an uptight person. However fate throws them together in a bizarre partnership when their friends are killed in an automobile accident and have designated them as the godparents entrusted with raising their infant daughter Sophie. No other relatives are available to take on this challenging responsibility, so Holly and Messer decide to hunker down and see if they can handle this needy toddler. They have to learn to coordinate their schedules, deal with poop and sleep deprivation and the stress of living in their friend's house, which seems to be haunted with their presences.

Their neighbors are couples who have been through the grind of raising kids and they have no shortage of advice. In addition, there is the burden of dealing with a snoopy social worker (Sarah Burns) who stops by at the most inopportune moments.

The best thing about Life as We Know It is the funny and snappy performance by Katherine Heigl as Holly. She has great comic timing and in one scene where she flirts with a handsome pediatrician (Josh Lucas) at her café, this actress shows why she is such an accomplished player of romantic comedy; she is pleasing to both the eye and the ear. Most of what happens in the story, directed by Greg Berlanti, is predictable. But thanks to the pizzazz provided by Heigl, there are plenty of bright comic moments to savor.