Behind the scenes, however, one story generated almost as much attention as the movie itself. According to IMDb trivia, Leto fully embraced his character throughout production, sending unusual “Joker-like” gifts to his co-stars, including one that Robbie unexpectedly decided to keep.

The Joker-Inspired Gift That Stayed With Margot Robbie

During the production of “Suicide Squad,” Leto remained in character even when cameras were not rolling, immersing himself in the Joker’s unpredictable personality. As part of that approach, he surprised several cast members with gifts inspired by the Clown Prince of Crime. One of the most memorable was a live rat that arrived for Robbie while she was preparing to play Harley Quinn.

Rather than being alarmed, Robbie decided to keep the animal. Speaking with E! News at the time, she explained that she named it “Rat-Rat” and felt it made perfect sense for Harley Quinn’s world. “If Harley got something from Joker, she’d probably cherish it,” she said.

The rat did not remain with Robbie forever, though. As her work schedule became increasingly demanding, filmmaker Guillermo del Toro eventually adopted the pet, giving the unexpected behind-the-scenes story an equally surprising ending.

Released in 2016, “Suicide Squad” was written and directed by David Ayer and assembled a cast that included Will Smith, Robbie, Leto, Viola Davis, Joel Kinnaman, Jai Courtney, Cara Delevingne and Adewale Akinnuoye-Agbaje. The picture followed a government task force made up of imprisoned supervillains sent on a dangerous mission in exchange for reduced prison sentences.

Despite receiving mixed reviews from critics, it earned more than $749 million worldwide and won the Academy Award for Best Makeup and Hairstyling, while Robbie’s Harley Quinn quickly became one of the DC Extended Universe’s most popular characters.