Despite the dark and brooding nature of a film like Mockingjay, behind the scenes the cast kept each other's spirits up, and minds psyched, by pulling pranks on each other -- on set and in their trailers.
At the massive Los Angeles premiere of The Hunger Games: Mockingjay – Part 1, held at the Nokia Theater L.A. Live, the stars stopped to talk with ET's Kevin Frazier, and revealed some of the wild and weird behind-the-scenes antics.
"It was the most awful combination of feelings in the world," Lawrence told ET. "It was like, Tiffany's!? Jeffrey! You didn't have to do that! And then I opened it… it was awful. And they were in my trailer for months, I couldn't get them out."
Actor Josh Hutcherson, who stars opposite Lawrence as Peeta in The Hunger Games franchise, explained why the cast loved playing jokes on her.
"She's just fun to mess with," Hutcherson told ET, laughing. "We just love giving her crap all the time, and whether it's a prank or just, you know, giving her a hard time, it's the best."