The introduction of the Quantum Realm in 2015's Ant-Man opened up new doors for the Marvel Cinematic Universe, as now there were other dimensions to visit. We revisited the Quantum Realm this past summer in Ant-Man and the Wasp, but since the sequel's release, many Marvel fans have speculated that this particular reality will also factor heavily into Avengers 4. According to Hank's actor, Michael Douglas, that is indeed the case, as he responded when asked if Ant-Man and the Wasp is directly connected to Avengers 4:
So there you have it, MCU fans. Your suspicions were confirmed by Michael Douglas during his appearance on On Air with Ryan Seacrest, although naturally, given how secretive these movies are, he didn't reveal any more details. We don't know if Douglas will reprise Hank Pym in Avengers 4, but evidently Kevin Feige, director Peyton Reed or one of the other Marvel Studios bigwigs clued him in on future happenings in this ever-growing franchise.
In Ant-Man and the Wasp, Hank Pym, inspired by how Scott Lang was able to make it into the Quantum Realm and get back out in the first Ant-Man movie, ventured into this strange reality to rescue his wife, Janet van Dyne, who'd been trapped there for over 30 years. Naturally there were some complication, but eventually the couple reunited and made it back to Earth. Unfortunately, both Hank and Janet, as well as their daughter Hope, were among the half of the universe snapped out of existence by Thanos, and Scott was consequently left trapped in the Quantum Realm.
It's expected that we might catch a glimpse of the Quantum Realm in Avengers 4 to show how Scott Lang gets back to our plane of existence, possibly by entering one of those time vortexes that Janet van Dyne told him to avoid. Beyond that, we haven't officially heard anything about how the Quantum Realm fits into the Phase 3 capper, let alone anything else regarding Avengers 4's story.
That said, there's been no shortage of fan theories in this area, from the surviving MCU heroes traveling to the Quantum Realm to go back in time to undo what Thanos did, to the people who were dusted at the end of Avengers: Infinity War not truly being dead, but somehow languishing in the Quantum Realm. Thanks to Michael Douglas, we now know for sure that the Quantum Realm is somehow integral to what goes down next year, and that we could see even more of it in Phase 4.
Avengers 4 opens in theaters on May 3, 2019, so keep checking back with CinemaBlend for continuing coverage. Don't forget to also look through our 2019 release schedule to learn what other major motion pictures come out next year.