Try as they might, fans remain in the dark as to what Marvel Comics character Jessica Chastain is playing in X-Men: Dark Phoenix. In September, the actor shot down rumors that she would take up the role of Shi’ar Empress Lilandra, and a new report indicates her character could belong to a rival alien species of the Shi'ar: the shape-shifting Skrulls.

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An Entertainment Weekly piece for X-Men: Dark Phoenix describes Chastain's role as "an otherworldly shapeshifter who comes into contact with Phoenix." The green-skinned Skrulls are known for their ability to shapeshift and assume the identities of their enemies, with some Skulls able to copy powersets as well.

The Skrulls played a minor role in the original "Dark Phoenix Saga" comics story, and their inclusion in the film would raise eyebrows, particularly considering the aliens will be the antagonists for Marvel Studios' Captain Marvel in 2019. Fans once assumed 21st Century Fox held the rights to the Skrulls since they were primarily Fantastic Four characters, but it has since been explained that they're one of the few properties that can be shared between Fox and Marvel Studios, similar to the speedster Quicksilver.

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Opening Nov. 2, 2018, X-Men: Dark Phoenix stars James McAvoy as Charles Xavier, Michael Fassbender as Magneto, Jennifer Lawrence as Mystique, Nicholas Hoult as Beast, Sophie Turner as Jean Grey, Alexandra Ship as Storm, Tye Sheridan as Cyclops and Kodi Smit-McPhee as Nightcrawler.