George Clooney decided to play a prank on his 'Monuments Men' co-star Matt Damon by loading his backpack with rocks for a gruelling hike scene.
While Matt was serious about working out on the set of 'The Monuments Men' in order to get in shape for the hiking scenes in the movie, George decided to play a trick on him by filling his backpack with rocks for the gruelling hike.
A source said: ''George got his idea for pranking Matt because he was so damn serious about working out every morning before shooting started. Bill Murray and John Goodman kept teasing him but Matt cracked that he'd be laughing when they didn't have stamina for the tough hiking scenes ahead.
''That's all George had to hear. He had the prop guys prepping packs for the hike fill Matt's with solid metal bricks, weighing about 50 pounds. The other guys' packs had lightweight padding but George told them to pretend they felt super heavy. By the end of the day Matt was sweating profusely. After the scenes were shot, Matt dropped his pack, opened it and everyone burst out laughing when the metal bricks tumbled out.''
'The Monuments Men' is currently being filmed in Cambridgeshire, east England.