Who was the voice of the alien Paul in the film titled "Paul"?

Seth Aaron Rogen (born April 15, 1982) is a Canadian-American actor, comedian, writer, producer, and director. Having begun as a stand-up comedian in Vancouver, he moved to Los Angeles for a part in Judd Apatow's series "Freaks and Geeks", and then got a part on the sitcom "Undeclared", which also hired him as a writer. After landing his job as a staff writer on the final season of "Da Ali G Show", Apatow guided him toward a film career. As a staff writer, he was nominated for a Primetime Emmy Award for Outstanding Writing for a Variety Series.

Rogen provided the voice and motion capture for the title character, a grey alien, in the science fiction comedy "Paul" (2011). The film also starred Simon Pegg and Nick Frost as a pair of geeks who help Paul escape from FBI agents.

"Paul" is a 2011 science fiction comedy film directed by Greg Mottola from a screenplay by Simon Pegg and Nick Frost. The film plot focuses on two science fiction geeks who meet an alien with a sarcastic manner and an appetite for alcohol and cigarettes. Together, they help the alien escape from the FBI agents who are pursuing him so that he can return to his home world. The film is a parody of other science-fiction films, especially those of Steven Spielberg, as well as to general science fiction fandom.