Here are the X-Men movies that should be rewatched before catching Dark Phoenix. Simon Kinberg's film is the swansong of Fox's 19-year film series about Marvel's mutant heroes and villains. With the purchase of Fox by Disney, the mutants will eventually join the Marvel Cinematic Universe, meaning Dark Phoenix is an unexpected last stand of this incarnation of the X-Men.

In Dark Phoenix, an incident in outer space unleashes the Phoenix Force within Jean Grey (Sophie Turner). Jean becomes corrupted by her world-breaking power and turns her into a threat to the X-Men, including her mentor Professor X (James McAvoy), and Genosha, the mutant island haven of Magneto (Michael Fassbender). Exacerbating the crisis is an unnamed alien played by Jessica Chastain, who is manipulating Jean for her own ends.

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Dark Phoenix is the 12th Fox X-Men movie and the fourth entry of the mainline X-Men series after X-Men: First Class rebooted the saga in 2011. It's also a cinematic do-over of Marvel Comics' The Dark Phoenix Saga, which was the B-plot of 2006's X-Men: The Last Stand, the final entry of the original X-Men trilogy. Thankfully, it's not necessary to rewatch all 11 prior X-Men movies and spinoffs, but fans who want to grasp the big picture may want to revisit the films that Dark Phoenix is a direct sequel to, all of which happen 10 years apart from each other. Here are the most important X-Men movies to know before seeing Dark Phoenix.

X-Men: First Class

X-Men First Class promo shot

Matthew Vaughn's X-Men: First Class depicts the inaugural X-Men's formation and how they stopped the 1962 Cuban Missile Crisis. It centers on the lifelong friendship/love triangle between Charles Xavier, Magneto and Mystique, and how it all fell apart due to their ideological differences. Although First Class takes place two decades before Jean Grey joins the X-Men, the patriarchal ways Xavier treats Mystique and his original students inform how Professor X would later try to control Jean to keep her powers in check, which is a lifetime habit Magneto calls him out for in Dark Phoenix.

X-Men: Days of Future Past

The time travel adventure of X-Men: Days of Future Past reveals how important Mystique is to the timeline as the X-Men try to stop her from causing a crucial death in 1973 that ignites the future extinction of mutants by the Sentinels. The film also introduces Quicksilver (Evan Peters) and establishes how Beast (Nicholas Hoult) has long been Professor X's loyal right-hand man; a relationship that is tested in Dark Phoenix. In terms of continuity, it will be important to contrast Dark Phoenix's ending against Days of Future Past's, which saw Wolverine's alter the original trilogy's timeline to give him a somewhat happy ending with the older Jean Grey (Famke Janssen).

X-Men: Apocalypse

Jean Grey Phoenix X-Men Apocalypse

Set in 1983, X-Men: Apocalypse directly sets up Dark Phoenix: it introduces Sophie Turner's Jean Grey and the rest of the current X-Men team, including Cyclops (Tye Sheridan), Storm (Alexandra Shipp), and Nightcrawler (Kodi Smit-McPhee). The X-Men save the world from Apocalypse (Oscar Isaac) but prior to that, the film depicts how Professor X has been trying help Jean, who can't control the sudden outbursts of her psychic powers. Later, Professor X urges Jean to "let go" and she unleashes the Phoenix Force for the first time in order to destroy Apocalypse. By the end of X-Men: Apocalypse, Mystique has finally returned to the X-Men and becomes their trainer, a prelude to Raven's ultimate fate in Dark Phoenix.

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For perspective, it might also be useful to rewatch X-Men: The Last Stand to compare how Dark Phoenix adapted the same material, which can be watched out of sequence with the above movies. However, since X-Men 3 is one of the worst films of the saga, it's understandable why fans would want to skip this step entirely. Instead, watching Logan again isn't a bad idea; not only is it a great X-Men movie, but viewers can examine how James Mangold's noirish Wolverine endgame compares to Dark Phoenix's tragedy.

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