It's been close to six years since the original Ant-Man film starring Paul Rudd came out and a lot of people probably don't realize it up to now but the action-packed film left a gaping plot hole concerning Darren Cross' version of the Pym Particle.
During the climactic sequence of the 2015 Marvel Cinematic Universe film, ex-S.H.I.E.L.D. member Mitchell Carson was seen snagging a briefcase full of the particles replicated by Cross. Carson was able to escape with the briefcase and he wasn't seen in any MCU project since.
Patented by Hank Pym, the said particle can give its user the ability to shrink or double in size with the use of a special suit. Hydra has been keeping a close eye on the formula for years so they could use it to their advantage and nobody seems to be bothered by the fact that Carson still has possession of the particles.
Actor Martin Donovan recently spoke with ComicBook about his Marvel character and according to him, he's quite unsure about his MCU future. "I am aware but maybe not to the extent that you've just described. I don't follow it closely, so I'm not aware."
Donovan added that he's still open to reprising the role and should Kevin Feige need him, his boys know where to find him exactly. "I wasn't aware that he's still a major subject and I don't know what the plans are for him, to be honest with you. I don't know where they're going with that. But yeah, I mean, I'm here. They know where to reach me. I'm sure the theories are quite wild."
Considering the character shares a lot of history with Hank Pym, the late Howard Stark, and even Hydra, Marvel Studios could easily set up Carson's return in the franchise. Ant-Man and The Wasp: Quantumania is the most obvious project for him to make his comeback, but with his Hydra ties, I also wouldn't mind seeing Carson appear in The Falcon and the Winter Soldier.
Ant-Man and The Wasp: Quantumania is slated for release in 2022.
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