Movie star Riggan Thomson (Michael Keaton), who became famous for playing iconic superhero Birdman in three successful installments but turned down a fourth one, has decided to stage a comeback by writing, directing and starring in a Broadway play.

Pressures mount leading up to the play's opening night. The day before the first preview of the play, he realizes he has to replace one of the actors, who is not up to the job. However, his replacement (Edward Norton), though famous and talented, comes with troubles of his own. Meanwhile, Riggan feels guilt about being a neglectful father to his daughter (Emma Stone), who's now working as his assistant. He also desperately wants the top critic in New York, who could make or break his play, to write a positive review, but he's worried the entire production will be a bust.