Arnold Schwarzenegger once found himself in big trouble as a young Austrian soldier after taking a tank out for a joy ride.
The Terminator star challenged a colleague to a race in the military vehicle while they were on break from work one night.
He tells U.S. late night Tv host Jimmy Fallon, "I said to my buddy, 'Let's see who is faster down this hill,' and we took off. We drove down this hill at least 40 miles per hour in the middle of the night. We didn't see where we were going, we were just crashing into trees and bushes.
"But, by the time we came down to the bottom, I beat him even though he had the more modern tank, but I realised the whole infantry, 15 guys that were standing on top of the tank, I totally forgot to tell them to get off. They were holding on and then they were falling off. I heard the screams the whole time.... When we came back we were punished."
The actor's commanding officers made him crawl through a six-hour mud obstacle course.
The prank didn't put Schwarzenegger off tanks - he owns the military vehicle he used as an 18 year old in the Austrian army, and often drives it at charity events to raise money for after-school programmes in the U.S.