The story follows two pot-smoking friends (Rogen, Franco) who get mixed up with a drug gang. Heard will play Rogen's girlfriend who makes him promise to give up marijuana. She later discovers he lied to her.
David Gordon Green is directing, while Judd Apatow and Shauna Robertson produce.
Heard appeared as the young Charlize Theron in North Country.
Pineapple Express was released August 6th, 2008 and stars Seth Rogen, James Franco, Danny McBride, Kevin Corrigan, Craig Robinson, Gary Cole, Rosie Perez, Ed Begley Jr.. The film is directed by David Gordon Green.