A little tidbit about Callum from an interview of Margarita Levieva, the lead actress in The Invisible.
MediaBlvd> Was anybody hurt in the stunts or the fights?
Margarita> I got hurt a few times, just falling the wrong way. My knees got hurt because I was running a lot. I started training, about a month before. I was running a lot, just to get myself back in shape. I ended up punching the guy who plays the detective, Callum Keith Rennie. I clipped the front of his nose.
Poor Callum.
Link to the interview.