Seth Rogen

After its cancellation, Apatow cast Rogen in his next series, Undeclared -- for which Rogen significantly contributed as a writer. Undeclared met the same fate as Freaks and Geeks and was canceled mid-season, but both series became surprisingly hot cult hits upon their DVD releases. Rogen went on to write for Da Ali G Show and take minor roles in Donnie Darko and Anchorman: The Legend of Ron Burgundy before being tapped by Apatow once again for a new project, this time on the big screen. The film was 2005's The 40-Year-Old Virgin, and Rogen's role as Steve Carell's well-meaning friend Cal finally brought him the large-scale success that made his comic skills a valuable commodity. Rogen also acted as co-producer on the film, which was touted as the funniest movie in years by critics and audiences alike, eventually grossing well over a hundred million dollars. There was obviously good chemistry on the set of The 40 Year Old Virgin, so Rogen signed on to appear in Apatow's 2007 comedy Knocked Up. Appearing alongside his old cast mates Paul Rudd and Leslie Mann, Rogen starred as a man who is forced to deal with serious unforeseen consequences when his one-night stand becomes pregnant. After the filmmakers' initial plans to cast Anne Hathaway in the opposite role fell through, Grey's Anatomy star Katherine Heigl signed on to star as the female lead. ~ Cammila Albertson, All Movie Guide