Falcon and the Winter Soldier has added a brand-new member to its cast. Eight-time Emmy winner Julia Louis-Dreyfus appeared in the penultimate episode as Contessa Valentina Allegra de Fontaine (but you can probably call her Val).

Although Valentina might not come across as dangerous (yet), she is one of Marvel's greatest supervillains.

RELATED: 'Falcon And The Winter Soldier': Wyatt Russell Trolls Fans, Suggests Chris Evans' Return

This Is A Wild Revelation From Marvel

Valentina walks in right after John Walker, the now disgraced Captain America is stripped off his rank and superhero title (and all future benefits) for killing a member of the Flag-Smashers in public...with his shield.

Val is well-aware that Walker has consumed the super-soldier serum, and tells him it has made him very valuable to certain people. She goes as far as naming it "the second-best choice" he has ever made in his life. The first? Answering the phone when she calls him in the future.

She's intimidating, wears killer heels and a purple streak in her hair and seems like someone who knows everything about everyone. Val is the surprise cameo fans were warned about, but only comic-book enthusiasts might understand who she really is. Valentina Allegra de la Fontaine made her comic-book debut back in 1967, and was one of the original S.H.I.E.L.D. characters. She is known to have dated Nick Fury. Her history was unknown for a long time, but in 2009, she was revealed to be a Russian sleeper agent who was working against S.H.I.E.L.D. all along. She's just another mole the good guys didn't know about. Jonathan Hickman's Secret Warriors comic series also saw the Contessa take up the mantle of Madame Hydra....which means the terrorist organization hasn't fallen apart yet. RELATED: 'Falcon and the Winter Soldier' Introduce Isaiah Bradley And Zemo In The Same Episode! [EMBED_TWITTER]https://twitter.com/GraceRandolph/status/1382973542678081536?s=20[/EMBED_TWITTER] Fans have noted the Contessa is a character who worked for HYDRA and a Russian spy group...which means she's one to watch. This also means there's a lot more coming from Veep star Julia Louis-Dreyfus! MCU's Kevin Feige has repeatedly discussed how the miniseries are setting up bigger projects for the future, but this revelation is an unexpected surprise. With just one episode left to complete the first season of Falcon and the Winter Soldier, it's hard to imagine what will happen next. Will John Walker finally have some humanity knocked into him? Will Sam become Captain America? Will Toress take on the mantle of the Falcon? One week until we find out!  NEXT: Marvel Fans Thrilled After ‘Falcon and the Winter Soldier’ Introduces The Future Falcon