WARNING: The following article contains major spoilers for Dark Phoenix, in theaters now.
Magneto's Brotherhood of Mutants in Fox's X-Men film franchise has more or less followed the same trajectory as the Marvel Comics source material. When they aren't depicted as run-of-the-mill villains, they're simply pawns manipulated by the Master of Magnetism to further his goals. Whether serving Ian McKellen's older Erik Lehnsherr or Michael Fassbender's younger one, the members of the Brotherhood were little more than cardboard lackeys. However, that changes drastically in Dark Phoenix, in which they're transformed into antiheroes trying to protect mutants and humans.
In the past, mutants like Mystique, Blob, Sabretooth, Juggernaut and Toad were employed by Magneto to help carve out a new world order, and as much as they said they were fighting for mutantkind, they were little more than terrorists. But when Sophie Turner's Jean Grey becomes possessed by a cosmic entity in Dark Phoenix and kills Mystique, she seeks absolution from Magneto on Genosha Island.
When soldiers are sent after Jean, however, Magneto must save them from her wrath. After she leaves Genosha, Beast reveals to Magneto they must kill the possessed Jean to prevent her from committing a genocide that will most likely result in the purging of mutants from the planet to make way for the alien D'Bari. The threat of extinction drives Magneto to rally his new, streamlined Brotherhood, not merely as flunkies or cannon fodder, but as a tactical unit similar to Charles Xavier's X-Men.
Rather than mindless terrorists, they're soldiers tasked with protecting the island and offering shelter to lost souls. This Brotherhood doesn't believe in war unless it's necessary; however, Magneto has little choice but to intervene, especially as they can no longer trust the manipulative Xavier.
While Professor X struggles to locate Jean using Cerebro, Magneto's soldiers shows how effective they are as an underground cell with eyes and ears all over. His Brotherhood is a global network that monitors the mistreatment of mutants, so Magneto can extract them, which allows him to more easily track Jean's movements. Genosha may not be a Sentinel's head or a technologically advanced hub as it is in the comics, Magneto will stop at nothing to safeguard his utopia of shanties and farmland.
He takes his kill-squad -- the psychic Selene and the hair-whipping Ariki -- and heads out with Beast, but this time it's no spectacle. They don't wear fancy costumes or make grand entrances; they travel in the shadows. Magneto does don the black version of his helmet, and unleashes his dogs of war reluctantly, with Beast joining for the assassination attempt. This time, Magneto is all about the mission, and pushes the X-Men to their limits when they intercept his team in New York.
Sadly, none of them is capable of stopping Jean. But Xavier realizes the Brotherhood views murder as a last resort, and reiterates how the team has changed. It's not like the Brotherhood of old, killing to make political statements. That's why it makes sense for the mutants to unite at the end to take on the D'Bari and their leader, Vuk, and help Jean to achieve redemption while reminding us that with the right guidance, the Brotherhood is just as effective as a force for good as the X-Men are.
Directed and written by Simon Kinberg, Dark Phoenix stars James McAvoy, Michael Fassbender, Jennifer Lawrence, Nicholas Hoult, Sophie Turner, Tye Sheridan, Alexandra Shipp, Kodi Smit-McPhee, Evan Peters and Jessica Chastain.