Honestly, though: Could you really give Harley Quinn, most popular Halloween costume winner (2015), a tattoo gun and trust her to not get into any mischief? Margot Robbie knows that's just not possible.
During a joint appearance with Tina Fey on the Late Show with Stephen Colbert, the Whiskey Tango Foxtrot costars started out discussing Robbie's adventurous nature, which segued into an anecdote about that one time she gave a Suicide Squad assistant a "swad" tattoo.
Watch her tell the story here, and please consider donating to Simon's laser removal fund. JK. You know he cherishes that thing.
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