As William Jackson Harper officially joins the MCU, many are now wondering if Ant-Man and the Wasp: Quantumania will feature a Reed Richards cameo. Serving as Paul Rudd's third standalone appearance as Scott Lang, otherwise known as Ant-Man, Ant-Man and the Wasp: Quantumania will officially kick off the MCU's Phase 5. The recent release of the film's long-awaited trailer offered the first glimpse at Kathryn Newton as Cassie Lang, while audiences were also introduced to another of Jonathan Majors' Kang variants, who is now primed to wreak havoc within the MCU.As Black Panther: Wakanda Forever prepares to officially close out Phase 4, all eyes are on Phase 5 and the incredibly exciting future that lies ahead. One of the MCU's most anticipated projects, Fantastic Four, has been at the center of social media speculation for some time, with MCU fans desperate to find out just who will take on the highly coveted roles of Marvel's First Family. Although not set to release until 2025, the MCU has been known to establish characters within other films prior to their own projects releasing, and Harper's recent Ant-Man 3 casting has left many curious whether the star could have a major future role to play.Related: Ant-Man 3’s Trailer Is Hiding The Movie’s Real Villain

After it was revealed that the actor had joined the cast of Ant-Man and the Wasp: Quantumania, Harper, who is best known for his role as Chidi Anagonye in The Good Place, confirmed the news himself on social media, leading many fans to begin intensely speculating just who he could be playing. The internet immediately erupted with theories that Harper could be taking on the role of Reed Richards, leader of the Fantastic Four. Many are now hoping his role in Ant-Man and the Wasp: Quantumania will be a cameo confirming this.

Who Is William Jackson Harper Playing In Ant-Man & The Wasp: Quantumania?

William Jackson Harper in Midsommar

Despite the excitement that surrounds Harper's new role within Ant-Man and the Wasp: Quantumania, no other details have been confirmed about his character. Original reports stated that the film will see him play the leader of a rebel group within the Quantum Realm, the key location of Ant-Man and the Wasp: Quantumania, though, naturally, this could be fabricated to hide the character's true identity. Harper has been among some of the more popular fan-casting choices for the role of Reed Richards, and as John Krasinski's appearance in Doctor Strange in the Multiverse of Madness confirmed, Marvel does, in fact, pay close attention to these popular casting choices.

While the fanfare that has surrounded Harper's casting could certainly end in disappointment, it's not entirely out of the realm of possibility that the actor could be the MCU's Reed Richards going forward. As audiences now continue to speculate about Harper's role within the MCU, it will be interesting to see if any more details emerge about his mysterious character prior to the film's release. With this latest Ant-Man installment set to have some major implications for the MCU's Phase 5 moving forward, there are only a few months to go until audiences learn whether Ant-Man and the Wasp: Quantumania will mark the official debut of Harper's Reed Richards.

Next: Fantastic Four Can Make An MCU Reed Richards Theory A Reality

Source: Twitter (Various, See Above)

Key Release Dates