In the first Doctor Strange film, Rachel McAdams played Christine Palmer. Stephen Stranger and Palmer had once been in a romantic relationship but had since moved past it. McAdams’ character helped the sorcerer in his battles against Kaecilius and Dormammu and served as balance to the mystic Strange. There has been no reason given for Rachel McAdams not returning for the sequel.
Details on the sequel are currently limited, though it is said to be Marvel Studios’ first true foray into the horror genre. Furthermore, the Disney+ series WandaVision will serve as its lead-in.
Doctor Strange in the Multiverse of Madness is scheduled to open on May 7, 2021.