Meet Grady, 25 years old. Fed up with life and of the way things are going. He works as maintenance staff at the airport. One day that he's pissed off at the whole world, he sabotages a key part of a plane engine in a way that makes it certain to crash at landing next time it takes to the air. And it's scheduled to fly tomorrow with 400 passengers on board. Damn his evil mind!
The next day, the plane is picked for a test flight as part of random quality control procedures. A chance of one in a hundred. The plane does crash at landing, killing the 3 crew members.