Riley’s “Deep Dark Secret” is one of the best running gags in Inside Out 2 – and the post-credits reveal has a subtle reference to a classic line from Back to the Future. Inside Out 2 has burst into theaters as the bona fide blockbuster of the summer, laying waste to any box office records in its path. Part of why the movie has been so successful is that its script is jam-packed with great gags. One of the sequel’s best gags is Riley’s “Deep Dark Secret.”

When Anxiety has Riley’s five original emotions bottled up, they’re taken away to be locked in “The Vault,” where all of Riley’s secrets are kept. There, they meet the main character of a pre-school kids’ cartoon that Riley secretly still likes, a video game character that she secretly has a crush on, and the “Deep Dark Secret” that Riley is hiding from everyone. In the post-credits scene, Riley’s deep dark secret is finally revealed – and it’s a Back to the Future reference.

Riley’s “Deep Dark Secret” Is That She Set The Rug On Fire (Like Marty McFly)

“If you guys ever have kids, and one of them, when he’s eight years old, accidentally sets fire to the living room rug… go easy on him.”

In the post-credits scene at the end of Inside Out 2, Joy returns to the Vault to pay a visit to the Deep Dark Secret. She tells him that it’s time to reveal the secret and he reluctantly tells her that Riley is the one who burnt the rug. Apparently, at one point, a hole was burned in Riley’s parents’ rug. Riley denied having done it and the mystery remained unsolved. But, according to the Deep Dark Secret, it was Riley who burned the rug all along.

This is a subtle reference to an obscure quote from Back to the Future. Just before Marty McFly heads back to 1985, he tells his reconciled parents, “If you guys ever have kids, and one of them, when he’s eight years old, accidentally sets fire to the living room rug… go easy on him.” Both Riley and Marty set fire to their parents’ rug at a young age. The difference is that Riley got away with it, while Marty was in a world of trouble.

Pixar Has A History Of Referencing Back To The Future

Back to the Future is one of Pixar’s favorite movies

The team at Pixar must be big fans of Back to the Future, because this Inside Out 2 gag isn’t the first time the studio has referenced Robert Zemeckis’ time-traveling comedy classic. In Toy Story, Rex repeats Marty and George’s line, “I just don’t think I could take that kind of rejection!” The final shot of Onward, in which Barley’s van takes flight and vanishes into the horizon, is based on Back to the Future’s final shot of the airborne DeLorean. It was even referenced in the first Inside Out movie when Bing Bong watched his hand disappear like Marty.