WARNING: The following contains spoilers for The Falcon and the Winter Soldier Episode 2, "The Star-Spangled Man," streaming now on Disney+.

Unfolding in the shadow of the nationwide rollout of John Walker as the new Captain America, the pursuit of the Flag Smashers in the second episode of The Falcon and the Winter Soldier nevertheless confirms for Sam Wilson and Bucky Barnes that the anti-nationalist group are definitely Super Soldiers. "How in the hell, after 80 years, are there eight Super Soldiers runnin' loose?" Sam asks, unprepared for where that loose thread will lead: to Isaiah Bradley, the first Black Captain America.

Introduced in Marvel's 2003 miniseries Truth: Red, White & Black, by Robert Morales and Kyle Baker, Isaiah was revealed to be part of the untold history of Project Rebirth, the U.S. government project that created Captain America. In a parallel to the real-life Tuskegee experiments, he was one of only five survivors among the 300 African-American soldiers used as test subjects in hopes of refining the Super Soldier Serum. Isaiah served alongside the other survivors in a short-lived black-ops unit in the early days of World War II before he was assigned a suicide mission: to destroy Germany's Super-Soldier program.

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Wearing a Captain America costume, and wielding the shield, Isaiah was successful -- defying the government's expectations -- but captured by the Nazis. Rescued by the German resistance, Isaiah returned to the United States, where he was court-martialed and imprisoned by a government determined to keep its experiments a secret. He served 17 years in solitary confinement before being pardoned in 1960.

The Falcon and the Winter Soldier changes the timeline of Isaiah Bradley's past, but the broad strokes of his life, and mistreatment, appear to remain the same. Played by Carl Lumbly (Supergirl, Justice League Unlimited), Isaiah is just one of the many secrets kept by Bucky Barnes (Sebastian Stan) over the decades.

Carl Lumbly as Isaiah Bradley in The Falcon and the Winter Soldier

To help answer his questions about the possible source of the Flag Smashers' enhanced abilities, Bucky takes Sam to Baltimore, to the home of a reclusive, aging man referred to onscreen only as Isaiah. Although they're initially turned away at the door by the man's grandson, Bucky gains entry after saying, "Tell him the guy from the bar in Goyang is here," a reference to a city in South Korea.

That quickly establishes a shared history, if not necessarily a pleasant one. It's quickly established that Isaiah and Bucky met during the Korean War, albeit while serving on opposite sides of the conflict.

"He's a hero," Bucky informs a confused Sam before subtly signaling Isaiah as another Super Soldier. "One of the ones Hydra feared the most, like Steve. We met in '51."

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"If by 'met' you mean I whooped your ass, then, yeah," Isaiah replies, with little hint of bravado. "We heard whispers he was on the peninsula, but everyone they sent after him never came back. So the U.S. military dropped me behind the line to go deal with him. I took half that metal arm in that fight in Goyang, but I see he's managed to grow it back."

More than 70 years after their fight, Isaiah wonders if the Winter Soldier has returned to kill him, which only begins to hint at his state of mind. When Bucky assures Isaiah that he's "not a killer anymore," the old man fires back, "You think you can wake up one day and decide who you wanna be? It doesn't work like that. Well, maybe it does for folks like you."

Bucky, Sam and Isaiah Bradley

"You know what they did to me for being a hero?," he continues. "They put my ass in jail for 30 years. People running tests, taking my blood, coming into my cell. Even your people weren't done with me."

That, of course, stands in stark contrast to the celebration of Steve Rogers as a national hero, and his elevation to near-sainthood, and the media circus surrounding his successor, John Walker. Heck, even Bucky, who murdered countless people as the Winter Soldier, is granted absolution by the government, to say nothing of fame and a veneer of respectability through his association with the Avengers. Isaiah Bradley, meanwhile, lives with his righteous anger in obscurity, scrubbed from the history books.

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That, naturally, doesn't escape Sam: "So you're tell me there was a Black Super Soldier decades ago and nobody knew about it?" It turns out that not even Steve Rogers knew about Isaiah, because Bucky never told him.

"I didn't tell anybody," Bucky confesses, "because he had already been through enough."

Indeed, 30 years of wrongful imprisonment is tragedy enough, but Isaiah's mention of "your people" hints it may have been even worse. "Your people," as Bucky clarifies to Sam, is Hydra, which would have become rooted within S.H.I.E.L.D. during Isaiah's sentence. However, whether that means Hydra, under the guise of S.H.I.E.L.D., was given unfettered access to Isaiah in prison is not yet clear.

What is clear, however, is that the introduction of Isaiah Bradley, and the revelation about his mistreatment, alters how we view the history of Captain America and the Super Soldier Serum in the Marvel Cinematic Universe, and may play a significant role in Sam Wilson's decision to reclaim the shield.

Directed by Kari Skogland, The Falcon and the Winter Soldier stars Anthony Mackie, Sebastian Stan, Emily VanCamp, Wyatt Russell, Noah Mills, Carl Lumbly and Daniel Brühl. A new episode debuts each Friday on Disney+.

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