The movie's tagline reads: "From Judd Apatow, Director of 'The 40-Year-Old Virgin' comes a comedy about a one night stand that became something more."
Heigl plays a young entertainment journalist with a fast-rising career whose life takes a detour after a drunken one night stand with a slacker (Seth Rogen) leaves her pregnant.

I hope it's rated R like The 40-Year-Old Virgin was. It ups the ante when you know they're not afraid to [Stewie voice] go there.
Also, Knocked Up's IMDB page says Heigl took the lead roll only after Anne Hathaway dropped out. Score!
Also, Knocked Up's IMDB page says Heigl took the lead roll only after Anne Hathaway dropped out. Score!



