Marvel's What If...? episode 4 shows how the Ancient One could return in Doctor Strange in the Multiverse of Madness. Introduced in Doctor Strange and played by Tilda Swinton, the Ancient One was the Sorcerer Supreme of the MCU, sworn defender of this plane of existence. She trained the Masters of the Mystic Arts to follow her teachings and used the Time Stone to probe the future looking for potential threats. "I've prevented countless terrible futures," she told Doctor Strange. "And after each one, there's always another. And they all led here, but never further."

The Ancient One died in Doctor Strange, a fate she welcomed even though she knew it would leave Earth vulnerable for a time. Although there were limits to the Ancient One's foresight - she couldn't see beyond her own death - somehow she had learned Stephen Strange would be the best of all Sorcerer Supremes, and she had the privilege of setting him upon his path. There is a sense in which the ongoing activities of Doctor Strange and the Masters of the Mystic Arts stand as her legacy. And yet, for all that's the case, there have been persistent rumors the Ancient One will return in Doctor Strange 2. The fourth episode of Marvel's What If...? has shown how that could happen.

Related: What If…? Episode 1 Teases Doctor Strange 2’s Rumored Multiverse Villain

Marvel's What If...? episode 4 is set in an alternate timeline where Stephen Strange didn't lose the use of his hands in a car crash - but, rather, he lost Christine Palmer, the love of his life. As in the main MCU timeline, this variant of Doctor Strange sought out the Ancient One and protected the world from Dormammu. Crucially, though, the heartbroken Strange went to insane lengths to resurrect Christine, traveling back to the moment of her death in an attempt to undo an absolute point in time and change the MCU's timeline rules again. Aware of the threat the universe would face because of Strange, this timeline's Ancient One created what she called "a psychic impression sent through a splinter in reality... an echo."

Ancient One and Doctor Strange in What If

This is how the Ancient One could return in Doctor Strange 2 without undoing her death. The Multiverse has been recreated in the MCU, Scarlet Witch is learning lessons from a book of forbidden magic called the Darkhold that damages the fabric of reality in the comics, and the chaos looks set to escalate into Spider-Man: No Way Home. It is no exaggeration to say reality is splintering, shattering apart, even in the mainstream MCU. Sensing this coming, the Ancient One could potentially send a psychic impression of herself forward in time to serve as a guide to her successor - just as in What If...?'s universe-ending episode 4.

This would allow Marvel to tell a comic-book-accurate version of the story in which Doctor Strange becomes Sorcerer Supreme. In Marvel Premiere #3-10, Doctor Strange found Earth threatened by a number of mystical beings who were apparently serving a monstrous force. Seeking out the entity behind this, Doctor Strange entered a Multiverse of infinite possibilities, traveling across the dimensions in search of his true enemy. It turned out to be the Elder God Shuma-Gorath, who set traps for Strange while attempting to break through the dimensional barriers and conquer the Earth. In the end, Shuma-Gorath possessed the Ancient One in an attempt to absorb his power, and Strange was only able to defeat the monster by killing him. This victory proved Strange was willing to go to any lengths to protect Earth - and was therefore worthy of being considered the Sorcerer Supreme. Rumors abound that Shuma-Gorath will be the villain of Doctor Strange 2. Should Marvel bring the Ancient One back, they could do something similar to the comics, with Strange ultimately forced to destroy his mentor to protect the Earth.

More: Doctor Strange 2: How Is The Eye of Agamotto Back After Thanos Destroyed It?

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