WARNING: The following contains spoilers for What If...? Season 1, Episode 4, "What If... Doctor Strange Lost His Heart Instead of His Hands?," streaming now on Disney+.

Part of the appeal of Marvel’s What If…? is a chance to explore the dark side of the Marvel Cinematic Universe without long-term repercussions. The comics that inspired the show certainly never hesitated to look at downbeat or unsettling outcomes, and “dark” is relative in the MCU, of course. The events of Avengers: Infinity War, Avengers: Endgame, WandaVision and Loki grappled with mass genocide, the corrosion of grief and the possibility that the universe may be under the control of a madman among other topics. Meanwhile, last week’s What If…? Season 1, Episode 3, “What If… the World Lost Its Mightiest Heroes?” dealt with the systemic and disturbingly easy execution of some of the most beloved figures in the MCU.

Even that, however, pales before this week’s episode: Season 1, Episode 4, “What If… Doctor Strange Lost His Heart Instead of His Hands?” Doctor Strange, arguably one of the most powerful of Marvel’s heroes, never lost his arrogance as the recent teaser to Spider-Man: Far From Home shows. And like many of them, his path to redemption involved being humbled and vowing to do better going forward. What If...? reveals how badly things can go wrong when a figure as powerful as Strange never has to face such a reckoning.

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The nexus event in this week’s episode entails the fateful accident that cost Strange the use of his hands. In this reality, Dr. Christine Palmer joins him on that car ride. The accident spares him and his hands, but kills her, driving him to seek out sorcery as a means of bringing her back from the dead. The drive is there, but the motive is all wrong. Considering that Strange has command of an Infinity Stone, the shift in his desires is chilling, and the ultimate impact is catastrophic. Indeed, once he has the Time Stone, he uses it to go back to her loss over and over again in an attempt to bring her back.

It becomes a grim variation of Groundhog Day, as he tries – and fails – to get the events right. It’s also an unsettling echo of Infinity War, and the 14 million possible universes the prime MCU Strange witnessed before locating the right sequence of events that allowed Thanos to be defeated in Endgame. Here, that same drive leads him back to the heartbreak of Dr. Palmer’s death over and over again, with no way out. It keeps Strange from healing and ultimately leads him to disaster.

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Doctor Strange in What If...? Episode 4

The episode holds so much power precisely because he’s the same Stephen Strange he always was. Viewers can keep hoping for him to turn away from the path he’s on – knowing that the character possesses the capacity to do so – only to watch him plunge deeper and deeper into madness. He can’t change Christine's death because it is an “absolute point” in time. The inability to accept what he cannot control, and the arrogance to assume that he doesn’t have to, is only slightly more prevalent here than in the prime MCU.

This episode’s variant universe is destroyed because of it. Only when it’s too late to change anything does Strange realize his folly, and by then, all he can do is watch reality unravel. It’s borderline nihilistic, worse than Thanos in many ways, and yet it was entirely preventable. An ostensible hero chose to do this because he wished to save an innocent life. But because he did so for his benefit instead of the world’s, he ends up wiping out all life in his reality. With Dr. Palmer alive, Strange is never driven to become Sorcerer Supreme, and the resulting paradox devours everything.

What If…? clearly intends to continue visiting such grim meditations, with Marvel Zombies and the possibility of a triumphant Ultron still to come. That darkness is part of the show’s unique appeal. Fans may not wish to see their heroes fall so dramatically, but the chance that it will happen gives the show a power that other MCU properties can’t hold. As grim as the Snap was, at least the heroes undid it. As Episode 4 proves, not every universe is lucky enough to have such a happy ending.

To see Doctor Strange's broken heart destroy his reality, the fourth episode of What If...? is streaming now on Disney+.

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