Hugh Jackman induced dehydration for forty-eight hours prior to filming scenes of Wolverine shirtless, losing water weight. He added that the method is dangerous, and no one should attempt it at home. Jackman used this same technique five years earlier to create his emaciated look for prisoner Jean Valjean in Les Misérables (2012).
Hugh Jackman stated in an interview that the only way he would reprise his role is if a crossover between Deadpool and Wolverine would happen. Both Deadpool movies have contained jokes aimed at Wolverine. Ryan Reynolds (Deadpool) is also close friends with Hugh Jackman. Hugh Jackman would be reprising his role as Wolverine in Deadpool and Wolverine as confirmed in 2022 by Ryan Reynolds and Hugh Jackman. Thus, Deadpool & Wolverine (2024) was born.
James Mangold stated that this movie is set in 2029 to avoid any conflict with the timeline established in X-Men: Days of Future Past (2014), but that his goal was to make a stand-alone movie that was not bound to continuing previous storylines or setting up sequels.
According to director James Mangold, allowing the movie to be R-rated was important, not so much for violent content, but for style: "For me, what was most interesting in getting the studio to okay an R-rating was something entirely different. They suddenly let go of the expectation that this film is going to play for children, and when they let go of that, you are free in a myriad of ways. The scenes can be longer. Ideas being explored in dialogue or otherwise can be more sophisticated. Storytelling pace can be more poetic, and less built like attention-span-deficit theater."