Credit: CBS

While promoting her latest film, Rough Night, Scarlett Johansson made an appearance on The Late Show with Stephen Colbert. The host covered a slew of topics including Scarlett’s party night with her 72-year-old doppleganger, their individual chicken wing chow-down style, and the amazing mega-scene from Scarlett’s other film, Avengers: Infinity Wars.

Stephen revealed he actually had the Captain America shield hanging upstairs. He then took Scarlett to the second floor of the set to get a better look at his Captain America shield. Once upstairs, he discovers something he didn’t know about his own set. There’s actually a safe behind the Captain America shield, and he has no idea what’s in it!

You can see the shock on Stephen’s face as he tries to pull the shield off the wall. He explains to the audience that’s the first time he realized there was a safe behind there. Scarlett jokes with the host and asks if Chris Evans is in the safe. Stephen literally has no idea what’s in there!

By the way, we love that Scarlett compares Captain America’s shield to “an old school trash can lid.”

The show couldn’t help but tweet this moment out. Of course, the internet had to know. Just what is in that safe?

They sure know how to spin a simple mystery into a complicated one! We love that this little incident has people spinning their wheels and their imagination. Some of the best ideas? The KFC recipe, the formula for Coke, and the lost Nixon tapes. All good guesses! We think Stephen Colbert should do an episode where he cracks open the safe with none other than Captain America himself, Chris Evans. Just a suggestion.

It kinda makes us wonder what other mysteries might be lurking on the set of The Late Show with Stephen Colbert.

(H/T Nerdist)