Finally, we know what was so funny to Blake Lively and Emily Blunt at the 2018 Michael Kors fashion show. 

The stars, who were seated next to one another at the New York City event, went viral after they were photographed laughing hysterically—while Zendaya appeared unenthused in the seat next to the Gossip Girl alum. Now, in Vanity Fair's latest lie detector video, the Edge of Tomorrow star admitted the very NSFW reason she and Blake were laughing.