After all, the late Heath Ledger won raves as the greasepainted villain in 2008's The Dark Knight, and even locked himself in a hotel room for a month before shooting to intensely immerse himself in the character.
But Leto's Joker tried to take it even further, staying in character throughout the entirety of filming, and behaving pretty bizarrely to his co-stars.
The 44-year-old Oscar winner sent creepy gifts like bullets, dead animals, anal beads, and used condoms to Suicide Squad co-stars Margot Robbie and Will Smith, who took it in stride. But co-star Viola Davis? Not so much. She told E! News that while she didn't actually meet Leto until filming had wrapped, she was ready to give him a gift of her own.
“Before that I was only introduced to The Joker…and I almost had my pepper spray out," Davis said. "You know, ‘You remember that bullet you sent me?’”
“He gave very interesting gifts,” Davis said. “I did not receive any personally, or else I would have got my husband — who was called ‘Headache Ball’ back in the day when he played football — and I would have said, ‘Take care of the Joker.’”
Forget Batman - looks like the Joker has an even tougher adversary to worry about.