Bruce Franklin, an assistant director and associate producer on the fourth Terminator film, said that Bale, a "consummate professional," just had a bad day. "If you are working in a very intense scene and someone takes you out of your groove. It was the most emotional scene in the movie," said Franklin. "And for him to get stopped in the middle of it. He is very intensely involved in his character. He didn't walk around like that all day long. It was just a moment and it passed.
Why so serious Mr. Christian Bale
YouTube - Christian Bale goes psycho on Terminator 4!!!
Listen here (Warning: Lots of F-bombs)
YouTube - Bale Out - Christian Bale Remix!
Listen here also (Warning: You might not stop laughing & dancing)