When a cure is found to treat mutations, lines are drawn amongst the X-Men—led by Professor Charles Xavier—and the Brotherhood, a band of powerful mutants organised under Xavier's former ally, Magneto.

'X-Men: The Last Stand' is divisive, exploring themes of acceptance and humanity. Visual effects, action, and Ian McKellen's performance are praised. However, pacing, underdeveloped characters, and messy storytelling are criticized. New characters and subplots are seen as overwhelming. Deviations from the source material and character handling, especially Professor X and Jean Grey, are contentious. Some appreciate its ambition and final battle.