Can the as-yet-untitled Avengers 4 give Captain America a happy ending? The grand finale of Phases 1-3, Avengers 4 is expected to be a film of scale and sacrifice that's unparalleled in the MCU to date. A common theory among fans is that the ending will be bittersweet, though, and will end on a far more optimistic note for Steve Rogers.

The central theme of the Captain America movies to date has really been sacrifice. In Captain America: The First Avenger, Steve Rogers proved his worthiness to become a super-soldier when he dove on top of a grenade to protect his fellow soldiers. By the end of the film, he'd sacrificed his entire life in the 1940s, awakening decades later in a time when almost everyone he knew was dead. As time passed, Rogers attempted to build a new life for himself as an agent of S.H.I.E.L.D.; but by the end of Captain America: The Winter Soldier, he'd made the decision to bring S.H.I.E.L.D. down. Even his attempt to create a team/family in the Avengers backfired in Captain America: Civil War, with the superheroes torn apart as a result of Zemo's machinations and Steve's own desire to prove Bucky's innocence. Time and again, Steve Rogers has been called to sacrifice everything for his ideals, and he's never been found wanting. Little wonder many viewers are eager for Avengers 4 to close with him rewarded for his years of heroism.

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But is it actually possible for Rogers' life to end on an optimistic note, or will he be called upon to make the ultimate sacrifice in order to defeat Thanos, the Mad Titan? Let's look at the possibilities.

Avengers 4 is Set to be Captain America's Final Film

Captain America Holding Back Thanos' Infinity Guantlet in Avengers Infinity War

Avengers 4 is the last film on Chris Evans's contract with Marvel Studios. Evans originally signed up for six films with Marvel; three solo movies and three ensembles. But the actor evidently found the experience of working with Marvel to be a satisfying one; he agreed to cameos in Thor: The Dark World and Spider-Man: Homecoming, and then extended his contract to cover Avengers 4. "I could have said after the third Avengers I was done," he reflected, "but they wanted to make the third and fourth Avengers films as a two-parter."

Captain America didn't ultimately play a particularly major role in Avengers: Infinity War, but according to screenwriters Christopher Markus and Stephen McFeely that was by design. "I will say there is less Steve Rogers... than you might expect in [Infinity War]," Markus explained shortly before the film's release. "Because they are such hard-bitten people, when a threat comes, they stand there and they take the threat. They don't crack. They don't whimper. They don't start talking about all their failed opportunities. So, there isn't that much to explore, especially when you don't have a lot of time. But there's a lot later."

The cliffhanger ending of Avengers: Infinity War was a useful narrative tool to tighten the focus of Avengers 4; as it stands, the finale will celebrate the original Avengers as they work to avert or undo the snap. It's generally believed Captain America and Iron Man will essentially be the focus of Avengers 4, a "Last Hurrah" for both Evans and Downey, who are believed to be departing the MCU together. The challenge facing Marvel is how to bring these stories to a satisfying close.

What Will Happen to Captain America In Avengers 4?

Avengers 4 is set to be both Robert Downey, Jr. and Chris Evans' final MCU film (at least for now). For Iron Man, it's possible Avengers 4 will come to an end with Tony Stark retiring, but no such option would ever be accepted by Steve Rogers.

Related: Avengers 4 Shouldn’t Kill the Original Avengers

As he observed in Captain America: Civil War, "If I see a situation pointed south, I can't ignore it. Sometimes I wish I could." That's led many viewers to believe Captain America's story can only be finished by his death in battle. A popular theory is that the Russo brothers will reproduce one of the most iconic scenes in Jim Starlin's Infinity Gauntlet comic, in which Captain America stood alone against the might of Thanos. The Mad Titan possessed the unlimited power of the Infinity Gauntlet, and he'd already easily bested Cap's most powerful allies. In spite of that, Rogers stepped forward boldly. "As long as one man stands against you, Thanos," he observed, "you'll never be able to claim victory." Needless to say, it didn't go well for the star-spangled Avenger, but that scene has come to define Captain America for comic book readers; a hero who will face overwhelming odds, and not falter, no matter what. It's easy to understand why many are keen to see this on the big screen.

But another theory, first proposed by Eman's Movie Reviews but now building traction among fans, is that the film will end with Steve Rogers traveling back in time and finding peace with his beloved Peggy Carter. There's strong evidence that Avengers 4 will be a time travel movie, so it can work in the plot. The idea would certainly be a fitting close to Steve Rogers's character arc, a satisfying way of bringing his story full circle. It would also explain why Evans has recently been a little more ambiguous about whether or not he could ever return to the MCU; Marvel isn't above making films set in the MCU's past (as next year's Captain Marvel proves).

Page 2 of 2: Will Avengers 4 End With Steve Rogers in the Past?

Captain America Steve Rogers Peggy Carter

Why Steve and Peggy Together is a Beautiful End to Captain America's Arc

Peggy Carter is the great lost love of Captain America's life. Captain America's one and only kiss with Peggy was a promise of the life he could have lived, one with a meaning beyond war. When he awoke in the 21st century, Cap's first thought was of Peggy. The dialogue pulled on the heart-strings like few other scenes in the MCU; "I had a date," Rogers reflected sorrowfully. When he learned that she was still alive, Steve headed straight to Peggy's side. But, of course, the relationship between the two could never be the same; he was stood at the bedside of a dying woman, decades older than him.

Avengers: Age of Ultron shone a sorrowful light upon Steve's continuing love for Peggy Carter. Scarlet Witch reached inside the minds of the Avengers and realized their darkest secrets and fears. Black Widow went back to her training, Thor saw Ragnarok, and Captain America... saw the war over. Steve was at a V.E. party, where a young Peggy finally offered him their dance. This was his ultimate fantasy, but one tinged with the inescapable truth that it could never be real. Steve was confused by the end of fighting and conflicted by how he'd lost his chance at a normal life. Wanda's plan was to strip Captain America's soul bare, showing him what could have been, reminding him that he has nothing to live for but the war against evil.

Related: How Avengers 4 Can Resolve Age of Ultron's Dreams

But does it have to be a falsehood painted with regret? Reuniting with Peggy on their date is evidently what Steve most desires, and this theory poetically gives him that resolution. It suggests that Steve Rogers will finally find peace and love, returned to a time when his friends were still alive, and taking Peggy Carter by the hand in a ballroom dance. It turns Wanda's nightmare vision into a promise of the future; the world Captain America believed he had lost is made available to him once again.

Can the MCU Really Leave Captain America Like This?

Steve returns with Bucky and the 107th in Captain America The First Avenger

In a character microcosm, this idea works. It allows Steve Rogers to bow out of the present day, with the potential for a new hero to take up his legacy. In the comics, both Falcon and Winter Soldier have had time as Captain America, and either could conceivably pick up the shield for Phase 4. Given the future of the MCU appears to involve embracing diversity like never before, the most likely is Falcon.

The first problem, though, is that this isn't necessarily a final end to Steve Rogers' arc. Marvel could potentially revisit the character by revealing his adventures in the 1940s, perhaps even showing the formation of S.H.I.E.L.D.. Making matters worse, once the Pandora's Box of time-travel has been opened in the MCU, there's no putting it back. Should the need ever arise, the Avengers can travel back to the past and ask Steve for help. This ending risks being a lot more ambiguous than it seems at first glance.

But the second problem is far more difficult; this theory risks contradicting the very nature of the MCU itself. Marvel movies exist within a single timeline. It's not perfect, but in general the timeline works - enough that a rough chronology of the entire MCU to date can be created. But returning Captain America back to the 1940s absolutely shatters this timeline - and certainly contradicts the Agent Carter one-shot and TV series. It essentially reboots the entire MCU, to the extent that we simply have no idea what's canon and what isn't anymore. It's true that Kevin Feige has referred to Phase 4 as "the next iteration of the MCU," but Marvel has also stressed that there'll be a sense of continuity to it as well.

Related: There's No Way Avengers 4's Time Travel Will Make Sense

As significant as this issue may be, it isn't necessarily fatal; that all depends upon the method of time travel Marvel choose to go with. For example, the film could suggest that Steve's decision to head back to the past creates an alternate dimension; his 1940s life doesn't exist in the MCU timeline at all. Indeed, Marvel may settle for only implying as much, trusting that the average viewer will simply enjoy a sentimental, poetic conclusion to Captain America's story and not worry too much about the temporal mechanics of it. Marvel's pseudo-science tends to be consistent, right up until the moment that it isn't.

Still, while this "happy ever after" ending is theoretically possible, there's little strong evidence to back it up. A more probable ending for Steve Rogers is a sacrificial death, one in which he makes a heroic last stand against Thanos, the Mad Titan. That would fit with the themes of sacrifice that have run through every Captain America movie to date, with Steve Rogers serving as the greatest inspiration for the next generation of Earth's Mightiest Heroes.

More: Which Characters Will Be Killed off Permanently in Avengers 4?

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