Since it was revealed that Anthony Mackie's Sam Wilson will not only be taking on the mantle of Captain America but will also be getting his own movie, with obviously the potential for more to come, speculation over how his story will pan out has been rife. With many options available for Marve when it comes to Captain America 4, the biggest question is still who will Sam's Cap be pitted against? If one theory is to be believed, then the MCU could see the arrival of original Captain America antagonist Red Skull's daughter, Sin, who appeared in the comic books in the 80s as an ally of HYDRA.
Originating on That Hashtag Show, the supposition is that Sin, whose real name is Sinthia Schmidt, will go up against the new Captain America in another addition to the generational feel of the series, considering we will have a new lead wielding the shield, and Emily Van Camp reprising her role of Sharon Carter, the niece of Steve Roger's love, Peggy Carter. If this does turn out to be the direction Marvel choose to go, and knowing how much they love to tie their movies together like a paper chain it has a good shout, then it would certainly go with idea of the MCU jumping forward to the next generation of heroes and villains.
The character of Sin was created by J.M. DeMatteis and Ron Frenz during their time helming the Cap's adventures during the 1980s. While you would think that this could have led to a nice little daddy/daughter team of evil, but as it transpired, Sin didn't really care for her father very much. However, this dislike didn't push her away from choosing a villain's path, and instead simply pushed her to try and beat him in the bad guy stakes. Could she be about to do the same on film? Well, some would argue that The Red Skull didn't exactly pose the greatest challenge to Steve Rogers, so a bit of one-upmanship could be no cards.
The Red Skull, who was played by Hugo Weaving in Captain America: The First Avenger way back in Phase One of the Marvel Cinematic Universe, but his ending in that movie, in which he was zapped away by the power of the space bending Tesseract, seemed a little bit of an anti-climax. Many thought he would return to the series in some form, but after almost a decade absence, no one expected his next appearance to be as the quite benevolent keeper of the Soul Stone in Infinity War and Endgame, although this time played by Ross Marquand. Part of the reason for this could be down to contractual issues between Marvel and Weaving, as he mentioned in a 2020 interview with Time Out that they "pushed back on contracts that we agreed on" and negotiations for him to appear again didn't go anywhere.
Perhaps bringing Sin into the series could well be a way of providing a more satisfactory ending to the legacy of the Red Skull in the MCU. With the announcement of Captain America 4 being in its infancy, and a whole schedule of Phase 4 movies taking us up to 2023 ahead of it, I expect it will be a long time before we see any kind of confirmation from Marvel over any rumours. As for who would potentially play Sin, then expect an even longer wait for that, but feel free to let the speculation start now. This news originated at ComicBook.com.