Simon Kinberg’s X-Men: Dark Phoenix will feature the mutant haven and iconic island known as Genosha.
According to Entertainment Weekly, it will act as a refuge for mutants, just as in the comics, with Magneto taking care of and leading his species there. “He’s set up this place for mutants that don’t have a home to go to and they can seek refuge there,” said actor Michael Fassbender on the island which first appeared in Uncanny X-Men #235 in 1988.
The last movie, X-Men: Apocalypse, ended with Professor Xavier and Mystique training Cyclops, Jean and a new team of youngsters, so this answers where Magneto went after he helped them defeat Apocalypse. However, a further twist was revealed by director Simon Kinberg, who in describing Genosha as "the mutant homeland," admitted that Jean (played by Sophie Turner) would be disturbing the peace and coming to Magneto for help for an unknown reason. “There’s a suspicion there on his part when she arrives," added Kinberg, while keeping major details close to his chest, as well as which other mutants will be there.
So far, we know that an accident in space results in Jean manifesting as the Dark Phoenix, Xavier's X-Men are now national heroes, and Jessica Chastain is playing a shape-shifting alien, leaving fans guessing what else Kinberg has planned in an adaptation that he has said will be more grounded than cosmic despite its galactic nature.
The influential 1980 epic “The Dark Phoenix Saga,” by Chris Claremont and John Byrne, chronicled the fall of X-Men founding member Jean Grey, driven mad by the enormous power of the cosmic entity known as the Phoenix Force, leading her to destroy a planet before she ultimately sacrifices herself to save the universe.
Arriving in theaters on Nov. 2, 2018, X-Men: Dark Phoenix stars James McAvoy, Michael Fassbender, Jennifer Lawrence, Sophie Turner, Tye Sheridan, Nicholas Hoult, Alexandra Shipp, Kodi Smit-McPhee, Evan Peters, Olivia Munn, and Jessica Chastain.