Johnny Depp didn't know he could sing. When Tim Burton cast him in the film "Sweeney Todd," the usually confidant actor was freaked out. He said in 2007, "I did these demos in my friend's garage studio because I didn't know if I'd be able to hit a note, to be honest, I really didn't. I did that and sent it to Tim and he said we're going to be okay. And then I became a bit more confident."