Corrected entry: How would McClane know that there were bad guys in the truck (in the aquaduct) when he shot through the door? Granted he had his hunch and whatnot, and the guys really WERE German baddies, but how could McClane have been sure? What if he'd shot two innocent bystanders?
redbaron2000
22nd Dec 2003
Correction: Because earlier on, the foreman for the aqueduct said that no one is working down the tunnel. It's also obvious because McClain saw the trucks design used in the heist previously.