X-Men: The Last Stand (2006)

X-Men: The Last Stand (also known colloquially as X-Men 3 or X3) is a 2006 superhero film and the third in the X-Men series. Director Brett Ratner took over when Bryan Singer dropped out to direct Superman Returns. The Last Stand revolves around a "mutant cure" that causes serious repercussions among mutants and humans, and on the mysterious resurrection of Jean Grey. The film is loosely based on two X-Men comic book story arcs: writer Chris Claremont's and artist John Byrne's "The Dark Phoenix Saga" and writer Joss Whedon's and artist John Cassaday's six-issue "Gifted" arc.
Following Singer's departure, the director's position was offered to Darren Aronofsky, Alex Proyas, Joss Whedon and Zack Snyder. Matthew Vaughn, who cast Kelsey Grammer as Beast and Vinnie Jones as Juggernaut, dropped out during pre-production and was replaced by Ratner. Filming started in August 2005, budgeted at $210 million, the most expensive film at the time of its release. X-Men: The Last Stand received mixed reviews from critics and fans, but grossed approximately $459 million worldwide, the seventh-highest grossing film of 2006.

Bryan Singer wanted to shoot the third film back-to-back with a fourth. On July 16, 2004, he left to direct Superman Returns, having only completed a third of a treatment focusing on Phoenix, and introducing Emma Frost, a role intended for Sigourney Weaver. In addition, Singer also wanted to showcase more characterizations of Rogue, Iceman and Pyro. Simon Kinberg and Zak Penn were hired the following month, and a studio executive read Joss Whedon's Astonishing X-Men story "Gifted", featuring a mutant cure, suggested it be the primary story. Matthew Vaughn came on board as director in February 2005, but left due to the rushed production schedule. Brett Ratner took over in June, and filming began on August 2, 2005.
A pharmaceutical company has developed an antidote to the mutant gene, provoking controversy in the mutant community. Magneto declares war on the humans and retrieves his own weapon: the telekinetic and telepathic Phoenix, who is the resurrected former X-Man, Jean Grey. After Phoenix kills Cyclops and Xavier, a final battle between the X-Men and the Brotherhood ensues, and Wolverine must accept that in order to save Jean from her second personality, he will have to kill her.