I'm writing a mystery-thriller about a guy looking for an old friend that has gone missing, and he gets involved with an Interpol investigation and some illegal arms dealers. I want some action, so my lead character is going to need to get his hands dirty. My problem is, he is just a normal guy. So do I make him a normal guy and set him up as being a bit handy, former athlete or something. Or do I go the well-tread former marine route? Both are going to be a little bit of a stretch, so I guess I'm asking which is the less silly of the two options?