Marvel's The Falcon and the Winter Soldier has been excelling in its quiet moments just as much as its action scenes, and nowhere is that more apparent than with a certain unexpected appearance in the life of newly disgraced and now former Captain America, John Walker. Comedy royalty Julia Louis-Dreyfus surprised everyone when she briefly came on screen in the Disney Plus series only to steal the entire scene, but it seems that surprise wasn't limited to the audience.

A few days after her featured episode premiered, Louis-Dreyfus tweeted out her own reaction to the cameo nobody saw coming. A shocked-face selfie with her character's business card and a simple "Yup" said all that needed to be said. Naturally, her followers quickly flooded her replies with their own enthusiasm, primarily shared through Seinfeld gifs. A particular instance of Elaine captioned with "Hail Hydra" captured the mood rather well.

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Louis-Dreyfus entered The Falcon and the Winter Soldier as Countess Valentina Allegra de Fontaine (just call her Val, but not out loud), a mysterious figure who assured Wyatt Russell's John Walker that he'd done the right thing when he killed a member of Karli Morgenthau's Flag Smashers. Taking command of both the room and the scene itself the moment she entered, Valentina gave John and his wife Olivia her card (which appeared to be blank) and urged him to pick up the phone when she inevitably called him.

The character of Valentina has a long history in Marvel Comics, becoming an imposing villain after spending a great deal of time as a S.H.I.E.L.D. agent. But it's unclear what her role will be in the Marvel Cinematic Universe going forward. In her episode, she told John she knew he took the super-soldier serum, which will likely come into play, suggesting she might attempt to recruit him to her cause as a sort of "Anti-Captain America." The mid-credits scene of John hammering together his own version of the iconic shield lends that idea some credibility.

Louis-Dreyfus is a big enough star that an appearance like this could even be a teaser for the character before she's introduced properly somewhere else. Even some of the stars of The Falcon and the Winter Soldier were unaware that she would be appearing. That seems to be standard procedure for a lot of cameos, just like in the biggest moment from season 2 of The Mandalorian.

On the other hand, seeing more of her is sure to shake things up even more for this already turbulent (in a good way) series. So now it's time to simply wait, and perhaps geek out just as much as Louis-Dreyfus herself.

The Falcon and the Winter Soldier is now available on Disney Plus.

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Source: Julia Louis-Dreyfus/Twitter