The reveal that Captain America has seemingly always been a sleeper agent for Hydra sent shockwaves through the Marvel community, and that's putting it mildly. Some fans are seriously, seriously upset that their longtime hero is now apparently a villain, thanks to writer Nick Spencer.
However, as is always the case with comics, there is likely much more going on than meets the eye. The final page of Captain America: Steve Rogers #1 without a doubt succeeded in its goal of getting people riled up and talking, but what comes next?
Nobody but Marvel and the creative team behind the project likely know for sure, but a number of convincing fan theories are already starting to hit the Web. The most prominent of these involve the cosmic cube and come from Rich Johnston via Bleeding Cool and comic journalist Brett White from Comic Book Resources. More specifically, it involves the girl Kobik, who is a sentient, living cosmic cube (don't ask).
For those not in the know, cosmic cubes in the Marvel Universe are artifacts of vast power that can be used for all kinds of purposes, including changing reality. They've recently played a large role in the post Secret Wars Marvel Universe.
Until recently, Steve Rogers was an aging, dying old man, having been drained of his super soldier serum in a fight with a villain named Iron Nail. That led to Sam Wilson (aka Red Falcon) becoming Captain America in Steve's stead.
Fast-forward a few months later, and Steve has had his youth and super-status restored to him thanks to Kobik, the before-mentioned living cosmic cube.
That brings us to the events of Captain America: Steven Rogers #1, where flashbacks show Steve's mother meeting a member of Hydra, who seems to take special interest in a young Steve despite having no real reason. It's implied Steve's mother then joins Hydra, and that this may have resulted in Captain America secretly being loyal to the Nazi organization all along. Hence why Captain America throws his partner Jack Flag out of an airplane while on a mission to save Dr. Selvig from Baron Zemo, who is searching for Kobik.
As these theories state, is it possible that one of of Captain America's oldest Hydra enemies have used the cosmic cube or Kobik in order to rewrite Steve's past, causing his mother to become recruited by Hydra and eventually leading to Steve's own indoctrination as well.
It seems like a definite possibility. It would certainly explain why the mysterious Hydra recruiter shown in the issue's flashbacks seems to know about Steve's superheroic future, despite Steve being nothing but a normal kid at the time. Who is behind the plot? Some theories believe Baron Zemo to be behind Captain America's fall to the dark side, while others believe it to be Red Skull. From our perspective, Red Skull seems to make more sense for a number of reasons.
One major reason is that it would be far from the first time the Red Skull has tried to eliminate Cap once and for all by manipulating the past. Shortly after Marvel's first Civil War event, Steve was seemingly assassinated, only for it to later be revealed that he was actually flung outside of time and space via a plan masterminded by Red Skull, all so Red Skull could take control of Steve's body and destroy America. It's also worth noting that cosmic cubes and Red Skull go way back, with the character having used them multiple times in the past in an attempt to destroy Steve. He used the cosmic cube once before to royally mess with Sam Wilson's timeline in order to defeat Cap. Red Skull has even transferred his consciousness into a cosmic cube before, showing just how efficient the villain is at bending the all-powerful technology to his will.
Perhaps Red Skull manipulated Kobik into changing Steve's past even as she rejuvenated his body? Or maybe he accomplished this plan via some other means? Maybe Red Skull used the cosmic cube to send the previously-unmentioned Hydra agent to the past for the sole purpose of recruiting Steve's mom? Either way, by somehow changing Captain America's past, Red Skull could turn his greatest enemy into his greatest ally.
These are all theories for now, but it's safe to say that the Captain America featured in Captain America: Steve Rogers #1 isn't the Steve Rogers fans know and love. Something about his history has been twisted, but fans will have to wait until the next issue for more definitive answers.