What Apatow flexed in The 40 Year Old Virgin, he honed in Knocked Up. In giving a great cast free reign with the script, the result isn't only a hilariously funny movie, it's a hilariously funny movie full of real people. Unlike a director who's also a writer but too in love with words (like David Mamet in The Spanish Prisoner) Apatow's concerned with letting his characters talk like people really do.

Man-boy doofus Ben (Rogen) probably can't believe his luck when he falls into bed with gorgeous TV presenter Alison (Heigl) one night after they've met at a hip club where she's been celebrating a career high.

A broken condom later and they find themselves inextricably linked in the most biological way, having to decide what to do with their unexpected bundle when they ordinarily would have no interest whatsoever in each other.

The overarching theme is one Kevin Smith handled with a little more smut in another Seth Rogen film, Zack and Miri Make a Porno – that amid the sexually saturated society or gender tensions we live in, there's real tenderness to be found along with the laughs.

But if you want to digest the film as a series of uproarious skits with great scripting and improv, it's easy to do.