Christian Bale struggles to communicate when he is in costume as Batman and resorts to using hand signals as the superhero mask hampers his hearing.
The British actor is currently filming his third appearance as the Caped Crusader in Christopher Nolan's The Dark Knight Rises alongside Tom Hardy as evil villain Bane.
Bale wears a full-facial headpiece to film his scenes as Batman, while Hardy also wears a mask on-set, and the Inception star reveals the two actors have been forced to find a new way to communicate as they can't understand each other from under their prosthetics.
Hardy tells Total Film magazine, "Anytime you put something on your face you're going to adopt a personality and a physicality that has nothing to do with acting. The only downside is you can't hear a word anyone is saying. Batman (Bale) can't hear me and he can't see me speaking so we sort of stand there looking at each other...
"We've been doing hand signals. I put my thumbs up when I finish my lines or I wink. And he sort of wiggles his fingers out of shot and I go, 'OK, now I've got to run up and kick you in the b**locks!'"