Jared Leto portrayed The Joker in the 2016 movie Suicide Squad based on DC Entertainment comics. He had only about 10 minutes of screen time, but the actor wanted to leave an impression in that limited amount of time, so he let the craze into his real life too.

Will Smith remembers that Jared Leto never talked to him outside the scenes they were filming. They didn't even greet each other or say goodbye. Will Smith also thought that it was wrong for Jared Leto not to come to rehearsals, but eventually he realized that he didn't have to as he didn’t even need to act like The Joker because he became him. Margot Robbie, who played the Joker's love interest, Harley Quinn, received a live rat from the actor and after getting over the initial disgust, she kept it as a pet. Viola Davis, who played the government official Amanda Waller, told Vanity fair, "He had a henchman who would come into the rehearsal room, and the henchman came in with a dead pig and plopped it on the table, and then he walked out. And that was our introduction into Jared Leto."