Johnny Knoxville has revealed he didn't play any jokes on the set of The Last Stand - because he was too intimidated by co-star Arnold Schwarzenegger.
The Jackass joker, who plays gun museum owner Lewis Dinkum, is quite the practical prankster but refrained from bringing out his bag of tricks in the action movie, which also stars Forest Whitaker, Jaimie Alexander and Luis Guzman.
"No, I didn't. I'm surely not going to prank Arnold. He bench-presses like 600 pounds so that could be very dangerous," he joked.
The 41-year-old added: "And I had too much on, trying to learn my stunts and lines."
Johnny particularly enjoyed helping Arnie fire a vintage machine gun for a shoot-off scene.
"We had a ball. Doing an action film, you get to do a lot of things you don't do in your ordinary life like firing a machine gun at the back of a school bus with Arnold Schwarzenegger," he said.
"I wouldn't say I have a favourite gun, but the Vickers gun was so much fun, being at the back of the bus - even though I was just loading the bullets in."
His previous experience with guns came in handy too. He has shot himself with guns before on the Jackass TV series.
Johnny explained: "I've shot guns before in the past, but on different films, you fire different weapons. You practise on each weapon before filming, you rehearse a lot so visually, you look like you know what you're doing. That's fun."
:: The Last Stand is in cinemas now.