'The Falcon and the Winter Soldier': Here's the story behind the major MCU cameo that blew up on Twitter (spoilers)

This post contains spoilers for the fifth episode of The Falcon and the Winter Soldier.

What's the deal with Julia Louis-Dreyfus? The Emmy-winning Seinfeld and Veep star started trending on Twitter early in the a.m. ... and it's not because there's an Elaine Benes spin-off coming to Netflix this fall. Turns out that Louis-Dreyfus is the newest citizen of the Marvel Cinematic Universe, making her first appearance in the penultimate episode of The Falcon and the Winter Soldier — an hour-long installment called "Truth" that sets up the show's final confrontation between the men who would be Captain America: John Walker and Sam Wilson.

Louis-Dreyfus pops up following Walker's disastrous appearance in front of a military tribunal, where he's discharged from the armed services and officially stripped of the shield that he bloodied on last week's episode. But he's still convinced he was in the right — and so does Contessa Valentina Allegra de Fontaine, who has been both an agent of S.H.I.E.L.D. and Madam Hydra in Marvel's comic book universe since comics icon Jim Steranko created her in 1967. "I would have killed the bastard, too," the Contessa tells a distraught John, adding that he has value to certain high-rollers outside of the military. And she makes it clear that she intends to keep in touch with him for future exploits in that "legal grey area" where she operates.

According to Vanity Fair, we won't have to wait for a second season of FAWS for another glimpse of Valentina. Louis-Drefyus is also in the big-screen Black Widow solo adventure that was supposed to hit theaters last May, until the coronavirus pandemic upended those plans. (It's currently scheduled to premiere theatrically and on Disney+ as a "premiere access" title on July 9.) The magazine also hypothesizes that she'll be central to the next phase of the MCU, potentially as the yet-to-be-revealed Power Broker or as the leader of the anti-Avengers, the Thunderbolts.

Over on Twitter, that speculation was a lot of yada yada yada compared to the revelation Julia Louis-Dreyfus is in the freakin' MCU.

The Contessa made an equally big impression on Walker. A post-credits scene reveals that the disgraced Cap isn't going lightly into retirement. Instead, he's following in the steps of his comic book counterpart by building his own Vibranium-free shield.

Meanwhile, Cap's actual shield is back in Sam's possession, and he seems ready to put it to use. Over the course of a rousing training montage, Steve's pal gets himself into fighting shape — without the aid of any super soldier serum — just in time for his first mission as America's (third) first Avenger: saving the Global Repatriation Council from a Flag-Smashers attack. In the final shot of "Truth," Sam opens a suitcase that many are assuming contains his Captain America suit.

Whether there's a new suit in that suitcase or not, Sam is well aware that Captain America's legacy comes with its own baggage. In the episode's most memorable scene, Wilson has a long talk with Isaiah Bradley about what the super soldier serum cost him. Instead of being crowned a hero, Isaiah was locked away from the world and only regained his freedom by faking his death. "They will never let a Black man be Captain America," Isaiah says. "And even if they did, no self-respecting Black man would ever want to be." Talk about your "Truth" bombs.

The only one who seems genuinely at peace with the ghost of Captain America at the end of "Truth" is Bucky. With no claims to Steve's shield or the suit, the former Winter Soldier is forging ahead solo, newly focused on making amends for his previously evil ways. He's even made peace with the Raft-bound Zemo, who is headed back to prison free of any grudges against Barnes. Wait, did we say solo? Twitter didn't miss the sparks that flew between Bucky and Sam's sister, Sarah.

Even thought the Falcon's wings are broken, you might say that Winter's Soldier's love life is taking flight.

The Falcon and the Winter Soldier is currently streaming on Disney+.

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