When Jessica Chastain was cast for X-Men: Dark Phoenix it came with the rumor that she would be playing Lilandra the Shi'ar Empress. Chastain posted a picture of a rainbow from her first day on the set of the new X-Men movie but debunked the Lilandra casting in a now deleted instagram comment that CBR was able to screenshot.

So she's not playing Lilandra, so who is she playing? Bleeding Cool's own Mary-Anne Butler has her own theory and it might surprise you; Emma Frost.

Beecause "dark phoenix" right, so we have to have her go dark before we get Lilandra. Theoretically. So I think Emma and Mastermind to help push Jean to the dark.

This is actually a pretty good guess because director Simon Kinberg has gone on record saying that he wants to keep the movie from getting too "intergalactic" and keep it grounded. If Emma is the one that triggers the Phoenix and Jean's transformation that would certainly keep the X-Men back on Earth.

Summary: Jean Grey begins to develop incredible powers that corrupt and turn it into a Dark Phoenix. Now the X-Men will have to decide if the life of a team member is worth more than all the people living in the world.

X-Men: Dark Phoenix, directed by Simon Kinberg, stars James McAvoy, Michael Fassbender, Sophie Turner, Jennifer Lawrence, and Nicholas Hoult. It will be released on November 2nd, 2018.