Avengers: Doomsday is inching closer, and the rumor mill says we may be dealing with a vengeful Dr. Victor von Doom played by Robert Downey Jr. Cute, casual multiversal terror. But there is another wildcard supposedly on the board: Captain Hydra. Most people immediately jump to Chris Evans as an evil Steve Rogers. I think the better bet is the guy the MCU has already shown will cross lines without blinking: Wyatt Russell's John Walker, aka U.S. Agent.
Why Captain Hydra makes more sense as U.S. Agent
Walker showed us exactly who he can become in The Falcon and the Winter Soldier: a government-made Captain America who cracked almost instantly under pressure, got the serum, and straight-up murdered a man with the shield. The MCU has already positioned him as a volatile antihero who craves validation and control. It would not take a lot to push him into something darker with the right puppet master.
Enter Hydra, which has been practically invisible since Avengers: Age of Ultron. Sure, we got a few winks and nods during the time-heist detours in Avengers: Endgame, but we have not seen Hydra operating at full strength in ages. If they have been hiding and rebuilding, Avengers: Doomsday would be a very on-brand moment for a comeback with a headline-ready monster: their own twisted Captain America.
The pitch: Hydra recruits Walker, then rewires him
Walker has taken hits from every direction: tossed around by the government and (from the sound of it) not exactly basking in trust inside the Thunderbolts either. He is constantly chasing the high of being the guy in the spotlight. Hydra knows how to sell a new identity. Promise him power, promise him purpose, and then swap in the fine print: he is theirs.
The scary version of this is Hydra combining an upgraded Super Soldier Serum with a neural leash inspired by Arnim Zola's tech. Not just a few trigger words like Bucky had in his Winter Soldier days, but a deeper brainwash that flips Walker's worldview and strips out independent judgment. Think: an obedient enforcer who follows orders on instinct. Weaponized patriotism, minus the brakes.
Why this actually protects Steve Rogers' legacy
Post-Blip, the MCU world is a mess: people popped back into a life that moved on without them, families and friends aged out of sync, and patience is thin. If there is no idealistic Captain America on the board, you can feel the mood getting meaner. Plenty of people still believe in Steve Rogers. They never really bought the government's replacement in U.S. Agent.
So if Walker becomes Captain Hydra, it does two things at once. One: it tracks with who he already is on screen, a guy who went dark the second he had the strength to do it. Two: it keeps Steve's image clean. The 'evil Cap' mantle lands on someone built for that turn, not the guy who jumped on a grenade before he even had powers.
Where to find U.S. Agent in the MCU
- The Falcon and the Winter Soldier (2021) - Premiered March 19, 2021. Marvel Studios. Streaming on Disney+.
- Thunderbolts* (2025) - Scheduled for May 2, 2025. Marvel Studios. Expected on Disney+ after theaters.
The Doomsday clock
Avengers: Doomsday is currently set for December 18, 2026. If Hydra really is getting the band back together, that is a very convenient stage for a corrupted super soldier to take a bow.
Anyway, that is the theory: Walker as Captain Hydra, Hydra as the hand on the wheel, and Steve's legend left untouched. If Marvel goes there, it would be messy, mean, and honestly pretty smart.