Logan is, first and foremost, a Wolverine movie. It’s also a western, a poignant character study, a story of a man reconciling with the inevitable, and a really great farewell for Hugh Jackman — and also maybe Patrick Stewart’s Professor X. Like the titular hero, Charles Xavier is quite different when we meet him again in Logan, haunted by a mysterious incident that is never fully explained, much to the film’s benefit. Director James Mangold would agree, as he’s revealed that the original script didn’t just allude to the incident, it actually showed it, which would have made for a much different film.

For much of Logan, the events that have led Wolverine, Xavier and Caliban (Stephen Merchant) to live in seclusion south of the border are somewhat mysterious. The X-Men are gone, mutants are dying out, and Xavier is heavily-medicated to control seizures which amplify his abilities and cause crippling psychic events that paralyze everyone nearby (except Logan and Laura, whose abilities slow the effects).

The “Westchester incident” is only briefly referenced a couple of times in the film; Westchester is, of course, where Xavier’s school is (or was) located, and it’s there that 600 people were seriously injured and seven others died. It’s fairly easy to deduce that Xavier was involved with whatever happened to the X-Men, even before the third act, when he experiences a moment of clarity and remembers what happened in Westchester. Although he doesn’t overtly explain it, it’s clear that Xavier experienced one of his seizures (probably the first) and inadvertently hurt and killed the very people he had committed his life to protecting.

It is devastating. And had James Mangold stuck with an earlier draft of Logan, we would have had to watch this painful event play out. In an interview with ComingSoon, Mangold says not only did he write that scene, but “at one point, it was even the first scene in the movie.” He goes on to explain why he decided to leave it behind:

It also made the movie about that. It was really interesting. It suddenly made the movie about X-Men dying, as opposed to allowing the movie to be a kind of unwinding onion, like allowing you to kind of enter the story and go, “Where is this going?” It was so large and loomed so large, and I felt like it also was still falling into the formula of the movies, with the big opener, that is setting up the mythology first. I thought, “What if we do an opener that leans into character first? Actually underplay those things?” Let them just feel like it’s more like a—what’s that? A normal thing, like it’s happened. And instead of underlining it, yeah. Just let it live in the background of all these characters.

That decision was for the best. Although there are exposition-heavy moments (the weirdly expertly-edited cell phone video from the X-23 experiments and basically every scene with Dr. Rice), Logan benefits from a lack of over-sharing, and not knowing exactly what happened at Westchester lends more depth to the sorrow of these characters. It’s not that the incident is unknowable; it’s that you can’t possibly know what it was like.

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