Fox Searchlight & New Regency have already tied down Michael Keaton, Emma Stone, Naomi Watts & Zach Galifianakis to star in Alejandro Gonzalez Innaritu’s Birdman, now Deadline report that Edward Norton has joined ship to star in the movie. The movie is described as a dark comedy which focuses on a former actor [Keaton], who once played an iconic superhero, as he mounts a Broadway play based on a Raymond Carver short story in a bid to reclaim past glory. However, the play’s egotistical leading man threatens to throw everything down the tubes. Emma Stone will play Keaton’s daughter, fresh from rehab & now his assistant. Watts plays an actress in the play. Galifianakis will play the production’s conniving producer, while Norton will star as the play’s egotistical leading man. Inarritu co-wrote the script with Nicolas Giacobone, Alexander Dinelaris & Armando Bo. Production is set to begin this April.