The District 9 star plays Stefan in the movie, which tells the tale of the iconic villainess from Disney's 1959 film Sleeping Beauty.
Jolie took her role as the evil witch seriously on set, but Copley reveals she was determined to have fun when the cameras stopped rolling.
He tells Access Hollywood, "It was amazing. We pranked each other like crazy. She is a very serious prankster. It is so intense and so controversial that I probably can't (reveal what she did). That's how intense it was.
"The gloves were off. We had an amazing time, two crazy people, doing crazy pranks. We got on super well and had a great time. I was like, 'Oh my God, she went there? Ok, that opens the door for me to go there!'"
Copley is renowned for playing jokes on his co-stars - he filled Matt Damon's trailer with trash, dirty clothes and fake limbs while they were working on new sci-fi movie Elysium.