Todd Sampson tries to defy gravity by scaling a 13-story building with nothing more than two vacuum cleaners strapped to his back; the invisible force of air pressure could mean the difference between life and death.

Todd Sampson releases a wrecking ball inches from his face in a dangerous experiment that tests the science of energy; as it hurtles back at him at 15 miles an hour, Todd must trust science to stop the wrecking ball before it crushes him.