Those are all problems that Riggan perceives and addresses in some fashion, but there are even bigger ones that he doesn't: The movie character that made him famous, a superhero costumed in a breastplate of molded feathers and a beaked mask -- the Birdman of the title -- has been taunting him in a shadowy monotone that actually sounds like Christian Bale's Batman, pestering Riggan to admit that his theater project, not to mention his whole life, is a sham.
Have I mentioned that this psychically distressing apparition may also have vested Riggan with the power to move objects, Carrie-like, with his mind? There's a lot going on in Birdman, though the somewhat harsh truth is that Riggan's agitation and torment are really just an excuse for the pyrotechnics of the filmmaking. Its novelty: The film appears to consist of a single long take, though Iñárritu and DP Emmanuel Lubezki have done some subtle piecing-together. Birdman's proficiency, the mechanically fluid kind, works against it in some ways. But none of that diminishes what Keaton does. His Riggan is like a grizzled nerve ending, frayed and whiskery but alive.