"I was looking for something more in my life to do. Dad was prior military, so I looked at joining the military," says Sgt. Lock, the son of a retired Air Force lieutenant colonel and a nurse practitioner.
"One of the beautiful things about this job is that you can never be the best," says Sgt. Lock, 42, who first won the award in 2003. "With every story that you do, it's a new beginning, it's a new rush of adrenaline, so I love trying to attain that never-ending goal, that you're never going to be best. But damn it, I'm trying."