Warning: Spoilers pertaining to Captain America, Captain America: Civil War and all things Cap-related, both in the comics and Marvel Cinematic Universe.
The Super Soldier Serum may well still course through his veins, but make no mistake about it: in the MCU, Chris Evans' Steve Rogers is no longer the Captain America we know and love.
Having dropped his vibranium shield at the climax of Captain America: Civil War, Rogers will indeed be moving on to pastures new in time for Avengers: Infinity War, slated for a 2018 release.
Civil War directors Anthony and Joe Russo, who are also making Infinity War, have now confirmed Rogers will no longer wield the shield. Joe Russo informed the Huffington Post about what the film's climax symbolized in terms of the all-American's character development:
“I think him dropping that shield is him letting go of that identity,” said Joe. “[It’s] him admitting that certainly, the identity of Captain America was in conflict with the very personal choice that he was making.”
Anyone unfamiliar with the finale of Civil War may wish to stop reading at this point, but those in the know will be aware it was Tony Stark who insisted Rogers "didn't deserve" the shield his father, Howard Stark, crafted.
A major crux of the film's plot was that Rogers sided with his old war buddy Bucky Barnes, a.k.a. the Winter Soldier, over poor Tony, who learnt late on in the plot his father was killed by Cap's old sidekick.
Just because Rogers is moving on doesn't mean there can't be a Cap; after all, the mantle has been passed down enough times in the comic fiction. Why would Marvel's Cinematic Universe be any different?
Here are a host of the top candidates to take on the star-spangled banner as their new garb, with some stretching the theory possibilities more than others.
1. John Walker (U.S. Agent)
Starting off with a less obvious choice, Marvel could venture completely outside the box by choosing to elect a previous unknown to the position of "Captain America" as a direct successor.
Cap was, after all, a government agent in his origins, so it would make sense the character of ever-loyal John Walker—a.k.a. U.S. Agent—could keep the persona of America's poster child under the watchful eye of the men in black suits.
It's likely we'll see Rogers' rabble of wanted superheroes take on a role similar to that of the New Avengers or Secret Avengers, doing their work in the shadows, while Stark & Co. can operate in the limelight as they please.
Therefore, introducing a new Captain America, one who will bend to the government's will and not break the status quo, may work to Stark's advantage.
2. Clint Barton (Hawkeye)
Given the lowly standing Jeremy Renner's incarnation of Hawkeye generally holds in the MCU, this theory will undoubtedly get its share of laughs, but hear us out.
Despite the advantages he gets from the Super Soldier Serum, Rogers is, in essence at least, a very human character, who just happens to have an assortment of incredible athletic abilities, as does Clint Barton (albeit not quite as incredible).
Barton is also well-accustomed to assuming other heroes' identities, having worked for a time as ninja Ronin and the size-altering Goliath in his days.
Hawkeye was actually considered by Stark as a potential successor to Rogers following his apparent assassination at the climax of the Civil War comic arc, and it was Barton who declined the role in a show of respect to his "deceased" friend.
In terms of logistics, Barton has the skill with projectiles to harness the shield's potential, but Renner's Hawkeye perhaps hasn't been developed strongly enough to take on such massive responsibility.
3. Sam Wilson (Falcon)
Now we get to one of those who has actually donned the stars and stripes in comic canon, Sam Wilson could follow the source material and take the shield on-screen, too.
It was in 2014, when Rogers lost the enhancements provided by the Super Soldier Serum, that Falcon was asked to assume the position of Captain America, and a fine job he did in the role as well.
Anthony Mackie was nominated for a Saturn award as Best Supporting Actor following his Marvel debut as Wilson in Captain America: Winter Soldier, but could he make that step up to the big time and fill Cap's boots?
The Avengers movie franchise has done a terrific job of building up the bond shared by Rogers and Wilson in recent films, and Mackie could be a splendid option to not only stay true to the comics, but revel in the role in his own right.
4. Tony Stark (Iron Man)
Think for one moment: "Who has Captain America's shield right now?"
Rogers drops it at Stark's feet in apparent agreement with his objection to the blue-eyed blonde keeping it, and it's now Tony's to seemingly do with as he pleases.
After all, it was his father's creation:
If the Stark/Rogers rivalry is indeed going strong by the time Infinity War rolls around, what better way for the former to get one over on his adversary than to add a certain vibranium shield to his arsenal and take on Cap's moniker as his own?
The Iron Patriot armour was first invented by Norman Osborn during the Dark Avengers story arc, but Stark and James "Rhodey" Rhodes have both made use of the red, white and blue on their suits.
The MCU could take a step further in the rivalry between Stark and Rogers by choosing to make Iron Man the United States' new high-powered shield-bearer, poetically combining both sides of the Civil War factions into one.
5. James Buchanan "Bucky" Barnes
And of course we couldn't discuss the topic of potential Captain America replacements before addressing the man who perhaps most famously took over from where Rogers left off.
It was following Rogers' Civil War demise in the comics that Barnes—once the young understudy to Cap during World War II—paid homage to his old companion by embracing the title as his own, and for a while, it worked to beautiful effect.
The one problem here might be that after sustaining substantial injuries in Civil War, Barnes is placed in rehabilitation/stasis in Wakanda, and we don't yet know the extent of those injuries or just how much he can expect to be involved straight away.
Either way, Cap's direct successor in the comics was always going to be a candidate for the MCU's version of that tale, and Sebastian Stan has formed enough of a cult following to potentially replace Evans in the position long term.