WTF Is the "Westchester Incident" in Logan?

In Hugh Jackman’s final Wolverine film, Logan, the aging mutant force-feeds his mentor Professor Xavier anti-seizure pills, telling him in whispers to forget about “what happened in Westchester.” Throughout the film, the characters mention this incident several times, and at a pivotal moment, Xavier’s eyes widen. “I remember,” he tells Logan. “I remember what I did.” An analysis of the Marvel comics pieced together to form Logan’s story explains what went wrong so many years before. Westchester, of course, is where Professor Xavier’s School for Gifted Youngsters is located.

Major spoilers for ‘Logan’ follow.

Logan is an effective combination of two major Marvel storylines: Old Man Logan and X-23. The first comic series, written by Mark Millar with art from Steve McNiven, tells the alternate history story of the mutant Wolverine at the end of his life. In this reality, called Earth-807128, supervillains have already won the day, and the children of familiar Marvel heroes now run wild in a desolate wasteland. Logan, who now longer goes by “Wolverine,” finds himself fighting off members of the Hulk Gang, an angry hillbilly clan made up of Bruce Banner’s descendants. Throughout his struggles, Logan tries to ignore a traumatic memory that’s revealed to the reader slowly over the course of several issues.

We finally learn that Logan, under the influence of the supervillain Mysterio, killed all of his X-Men mutant friends decades before the comic opens. That mass murder is the last time he allows himself to use his adamantium claws, and he can’t forgive himself for it.

The emotional trauma and the fact that all the X-Men were killed horrifically remain the same in Logan, though the film switches the blame from Logan himself to Professor X. Mysterio had nothing to do with the “Westchester incident” in Logan’s universe, though: Xavier’s degenerative brain disease, as we see onscreen, causes him to erupt into uncontrollable seizures. Because he’s a telepath, his seizures manifest in the physical world by painfully holding normal people completely still. Mutants like Logan and Laura are somehow less affected by Xavier’s telekinetic waves of power, and they’re able to struggle through space with great effort.

In the scene set in the casino hotel, Logan and Laura cut off Xavier’s seizure by injecting him with medication. When the dust has settled, Logan says that left untreated, Xavier’s seizure would have killed everyone in the building. Though Xavier doesn’t remember why at the moment, he’s overcome with grief as Logan whisks him through the casino lobby. “I’m so sorry,” he sobs over and over, watching normal people around him hold their skulls and move woozily toward the building’s exit. We don’t see in flashback how Xavier accidentally killed off his mutant students, but the casino scene gives a haunting hint at what it must have looked like.

Though Logan can’t blame Xavier for the disease, Xavier does blame himself for what happened. In that sense, Logan borrows the emotional spine from Old Man Logan while making room for another fan favorite, Xavier, onscreen alongside Hugh Jackman.

Logan hits theaters March 3.