n Dark Phoenix, the latest film in Fox’s X-Men franchise, Jessica Chastain’s mysterious villain may have a deeper connection to Professor Charles Xavier than we realized. While Chastain has long been speculated to play anything from a gender-bent Mister Sinister to Shi’ar Empress Lilandra to the Skrull queen Veranke, her role likely hits a little closer to home. In fact, we believe she may be Xavier’s dark shadow: his “twin” Cassandra Nova.

In the comics, Nova has a rather complicated history. The character debuted in Grant Morrison and Frank Quitely’s New X-Men #144 as a “mummudrai,” or a parasitic life form that exists on the astral plane. In an effort to create a body of her own, she copied Xavier’s DNA while he was still in the womb; this made her biologically his twin. Xavier killed her before they were born, resulting in a stillbirth, but Nova’s astral form persevered. She eventually rebuilt herself a body using the telepathic abilities she copied from Xavier and became hellbent on destroying everything he held dear, believing she existed in a universe where only she and Xavier were real and everything else was an illusion.