[TOMT]someone cheerfully allowing themselves to be horribly injured in a tv show

There was a tv show or movie in the past few years (it could have been older, but I saw it recently) where someone wanted to either break or cut off someone's arm, and they said no. Then they turned to another character and said "what's your excuse?" And the person said "ain't got one," and stuck out his arm. This is driving me crazy, because I have the feeling that it's something really well known, but Google turns up nothing for me.