Russell Crowe threw a log at Prince Andrew on the set of Robin Hood.
Prince Andrew was visiting the set of Ridley Scott and Crowe's new movie when they were filming in Windsor Great Park when Crowe played the prank.
Speaking to Live Magazine Crowe said: "I'm happy he caught the log. It was an instinctive thing - it's like when you are playing sport.
"I threw it where he had the best possible chance of catching it. The thing is, if I'd thrown it too hard I'd have made a complete jerk of myself, and it wasn't about doing that.
"It was about showing a group of Englishmen, who were a little bit overawed with their prince being there, that's he's a bloke and is ready for a bit of fun.
And the Oscar winning actor admitted that after spending time with Prince Andrew on set he liked the royal's sense of humour.
"I really liked him. He's smart, knowledgeable and very inquisitive. He told a funny story too. He said, 'I was having dinner with my mother, and I asked her if it was appropriate that I wear a suit when visiting the film set.'
"And his mother, who is the Queen after all, said, 'No Andrew, if you turn up in a suit people will think you're a ninny (fool).' Whatever I thought I knew about him changed completely. He was charming."
Crowe is back on the big screen this week as famous outlaw Robin Hood in a new telling of the classic tale by filmmaker Ridley Scott.
Robin Hood is released 12th May.
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