At this point, it's become clear that The Falcon and the Winter Soldier is drawing inspiration from a particular story arc in the Captain America comics. The storyline in question happened in the late 1980s and involved U.S. Agent taking Steve Rogers' place as Captain America. The Disney+ Super Bowl TV spot confirmed the fan theory that U.S. Agent would become Captain America in The Falcon and the Winter Soldier.

The Falcon and the Winter Soldier will explore the ramifications of Captain America's Avengers: Endgame ending, which saw Steve Rogers (Chris Evans) select Falcon (Anthony Mackie) to become the new Captain America. Disney+'s first MCU show brings back Falcon and Bucky Barnes (Sebastian Stan) for a team-up that will somehow involve other characters from the Captain America trilogy, including Sharon Carter (Emily Van Camp) and Baron Zemo (Daniel Bruhl), who will finally receive his iconic purple mask.

Related: Disney+ Has Marvel's Most Comic-Accurate Costumes: Here's All Of Them

The Falcon and the Winter Soldier will also feature the MCU debut of Marvel Comics superhero U.S. Agent, aka John Walker, who will be brought to life by actor Wyatt Russell. In Marvel Comics, U.S. Agent wears a black Captain America costume and wields a shield similar to Steve's. Known for his aggressive and sometimes antisocial behavior, U.S. Agent distinguished himself as a key member of the West Coast Avengers during the late 1980s and early 1990s. It appears that one of his stories, which happened before he took the name "U.S. Agent," will serve as the basis for Marvel's Falcon and the Winter Soldier series.

How U.S Agent Became Captain America In Marvel Comics

John Walker Captain America Going Berserk in panel from Marvel Comics

When Steve Rogers decided to step down as Captain America, the government looked for a replacement, and believed they had found a suitable candidate when they discovered John Walker, a man who bought his super strength off the black market. He was currently operating as the costumed vigilante Super Patriot when he was first approached about becoming the new Captain America. After accepting the position, Walker was taught how to use the shield by Taskmaster and given his own "Bucky" in the form of a new hero named Battlestar. The new Captain America and Battlestar fought crime as a duo, and began taking on terrorists and other threats. For a time, Walker wanted to emulate Captain America and prove that he was worthy of being his replacement, but he was less idealistic than Steve and proved too aggressive for that to work.

Unfortunately, Walker was unaware of what being Captain America meant for himself or for his family. He quickly became a target of very powerful people, and before long, his parents were murdered by his enemies. This, along with other incidents, contributed to U.S. Agent having a mental breakdown. He ended up going on a murderous rampage and killing the people he held responsible. Meanwhile, Steve Rogers moved on from being Captain America and found a way to continue being a superhero. He took up the mantle of "The Captain" and began carrying a new shield created by Tony Stark. In one of his adventures as the Captain, he was forced to rescue his successor, Walker, from the villain Flag-Smasher.

How Captain America Defeated U.S. Agent In Marvel Comics

Captain America US Agent The Captain John Walker comic

As the John Walker storyline stretched on, it became apparent that a showdown between the two Captain Americas was inevitable. It finally came to pass, when the Red Skull infiltrated the government and hatched a scheme that would turn the two against each other. He showed Steve Rogers that Walker had killed people in cold blood, and fooled Walker into thinking that Steve was the true mastermind. The two engaged in an epic fight that lasted for quite a while. The problem for Steve was that Walker was several times stronger than him, making it incredibly difficult to do any considerable damage, and the force of Walker's blows was almost too much for Steve.

Related: Has Falcon Taken Super Soldier Serum To Become The New Captain America?

As their fight continued, Walker's mental issues — brought about by Red Skull's scheming, as well as everything the super soldier had been through — became more apparent as Walker grew increasingly savage and reckless. He tried to strangle Steve to death, but was finally knocked unconscious by Steve. Following his tiring battle with the new Captain America, Steve confronted Red Skull and defeated him. In the aftermath of the fight, Walker came to his senses and made amends with Steve Rogers. The government tried to reinstate Steve, and with some convincing by Walker, Steve accepted and resumed his role as Captain America. Later, John Walker decided not to walk away from being a superhero, and took up Steve's "The Captain" costume to become U.S. Agent.

How U.S. Agent Becomes Captain America In The MCU

How will The Falcon and the Winter Soldier adapt U.S. Agent's origin story? Netflix's Jessica Jones already adapted a variation of the Power Broker story, so Marvel may instead recreate Steve's super soldier serum or develop a whole new formula. But why choose Walker for this project? Set photos indicate that U.S. Agent will be a highly decorated war hero, so his service in the military could be why he gets the job. This would set him apart slightly from the comic book character, who never saw action while in the  U.S. Army.

Obviously, the biggest difference between the comic and The Falcon and the Winter Soldier is Captain America himself. The comic book version is a Steve Rogers story, but Chris Evans' exit from the MCU forces Marvel Studios to put the emphasis on different characters instead. In the show, it will be Falcon, and not Steve, who will need to claim what's rightfully his and become Captain America.

The way that Walker is being paraded around as Captain America during a football game in The Falcon and the Winter Soldier's Super Bowl TV spot suggests that the government is trying to hype him up as a new American symbol. The question is, will he, like his comic book counterpart, fail to live up to the ideals and standards of his predecessor? If so, Falcon and Winter Soldier may have to team up to defeat him and save Captain America's legacy from being tarnished.

More: Everything We Know About The Falcon & The Winter Soldier TV Series

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