Ant-Man and the Wasp: Quantuamnia (2023) writer Jeff Loveness was initially hired to write the screenplay for the film in 2023. However after the Ant-Man sequel underperformed at the box-office, Loveness was replaced with Michael Waldron. Waldron was previously set to write Avengers: Secret Wars (2027) as well. In San Diego Comic-Con 2024, however, Stephen McFeely was announced as the new screenwriter for Avengers: Doomsday. McFeely previously co-wrote the Captain America films and Avengers: Infinity War (2018) and Avengers: Endgame (2019) in the Infinity Saga.
