Marvel Studios has added William Jackson Harper to the star-studded cast ofAnt-Man and the Wasp: Quantumania. The third official installment into theAnt-Manfranchise will be Harper’s introduction to the Marvel Cinematic Universe in a role that the studio is closely guarding.

Ant-Man and the Wasp: Quantumaniawelcomes Harper to star alongside a truly incrediblecast that includes Paul Rudd, Michelle Pfeiffer, Evangeline Lilly, and Academy Award-winner Michael Douglas. The four talented staples of theAnt-Manfranchise will be reprising their roles from 2015’sAnt-Manand 2018’sAnt-Man and the Wasp. Harper, however, is not the only newcomer and will be joined by Kathryn Newton as Cassie Lang and Jonathan Majors, starring as the antagonist, Kang the Conqueror.

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Ant-Man and the Wasp: Quantumaniawill usher in Phase 5 for the MCU and will follow Ant-Man, played by Rudd, and his family as theybattle Kang the Conquerorin the Quantum Realm. Harper’s role in the film is being kept tightly under wraps, so it is unclear whoThe Good Placestar will be portraying. Harper’s comment on the casting via Twitter was subtle, so it looks like audiences will have to wait for the film to see the secretive role that the studio is keeping locked behind closed doors.

WithAnt-Man and the Wasp: Quantumania’s release drawing close, the casting comes as a bit of a surprise to many fans, but the news could hint at something that fans have patiently awaited. Casting for theFantastic Fourhas been a topic of serious conversation ever since Marvel Studios announced the film. Fans were hoping to learn more news surrounding the film at this year’s San Diego Comic-Con, but details remain limited. Some have speculated that theFantastic Fourorigin could potentially involve the Quantum Realm, which has some assuming that Harper will bethe MCU’s Reed Richards. Nothing official from Marvel Studios has surfaced, but the speculation ignites some excitement for what’s to come in the upcomingAnt-Manadventure.

Harper last appeared in thePeacock original comedy seriesThe Resort, starring alongside Cristin Milioti. It is unclear how long Marvel Studios will keep Harper’s role inAnt-Man and the Wasp: Quantumaniaa closely guarded secret, but it is clear that the role is important enough not to be spoiled. As more news surrounding the film surfaces, audiences may receive some insight into his potential contributions to the Quantum Realm adventure, but until then, speculations will surface, which the studio will undoubtedly refuse to address.

Ant-Man and the Wasp: Quantumaniawill hit theaters on August 06, 2025.