Mos Def has been cast in the science fiction movie “The Hitchhiker’s Guide to the Galaxy.”The movie is an adaptation of the famous Douglas Adams book of the same name.”The Hitchhiker’s Guide to the Galaxy” spawned four follow up books as well.Mos has been cast to play an alien named Ford Prefect, sidekick of earthling Arthur Dent, played by Martin Freeman.Mos Def’s character escapes from earth before it’s destruction and wind up traveling throughout the universe.Filming starts in April in London.