There have been plenty of theories concerning how Ant-Man’s Quantum Realm could affect the future of the Marvel Cinematic Universe. Now, there is confirmation from Marvel’s 10 Anniversary MCU book that the studio plans to explore it in the future. An excerpt from the book includes the following statement from Marvel’s Kevin Feige as posted by ComicBook.
“At the end of Ant-Man we followed Scott Lang into the Quantum Realm for the first time. We were beginning to peel back the onion that would later be completely peeled back in Doctor Strange as we go into the multiverse. So that was our little test into that. But now the Quantum Realm is a whole other territory that we can play with to tell our stories. This Quantum Realm is much larger than we ever imagined, and there are all sorts of adventures to be had at that level, which perhaps we will explore in another film.”
There have been rumblings that the Quantum Realm could have major implications in upcoming films like Captain Marvel and Avengers 4. Although, in both cases, it hasn’t been confirmed.
One possible avenue could be a way to introduce new characters to the Marvel Cinematic Universe such as The Fantastic Four (replacing the Negative Zone), Squadron Supreme, Atlas/Atlantis, and even possibly the god-like team The Eternals. Concerning the former, that seems like it would take a little longer to add the Fantastic Four due to the merger and that studio isn’t likely looking to their reboots.
Although, there is a good chance that something like Ant-Man 3 will be mostly set there.
We’ll have to keep an eye out during future films to see if the Quantum Realm will indeed play a large role in these upcoming stories.