In "X-Men: The Last Stand," Jean Grey undergoes a transformation into the Phoenix after being resurrected from her death in "X2: X-Men United." As the Phoenix, she possesses immense power but struggles to control it, leading to destructive behavior. Ultimately, her powers pose a threat to both the X-Men and humanity. In a climactic confrontation, Wolverine is forced to kill her to stop the chaos she unleashes, ending her life once again and highlighting the tragic consequences of her immense abilities.

Nightcrawler, played by Alan Cumming in "X-Men: The Last Stand," is absent due to a combination of creative decisions and scheduling conflicts. Director Brett Ratner wanted to introduce new characters and focus on the storyline surrounding the "Cure" and the conflict between mutants and humans. Additionally, Cumming had commitments to other projects, which made him unavailable for the film. Consequently, Nightcrawler did not return for this installment of the franchise.

"X-Men: The Last Stand," released in 2006, received mixed reviews from critics and fans. While it features impressive action sequences and visual effects, many felt it did not live up to the standards set by its predecessors, "X-Men" and "X2: X-Men United." The film's storyline, which includes the controversial "Dark Phoenix" arc and the introduction of the Mutant Cure, was criticized for pacing and character development. However, it still holds a place in the franchise for its ambitious themes and ensemble cast. Overall, opinions on its quality vary widely.

In "X-Men: The Last Stand," a cure for mutation is discovered, sparking a divide among mutants. While some, like Beast and Professor X, support the cure, others, including Magneto and Mystique, oppose it fiercely. Jean Grey returns as the powerful Phoenix after being resurrected, leading to chaos. Magneto seeks to use her power to attack humans, while the X-Men, led by Wolverine and Storm, try to stop him. The film culminates in a dramatic battle, resulting in significant losses for both sides and the ultimate sacrifice of several key characters.