Watch Jimmy Kimmel Spoil Major Dark Phoenix Death in Front of Cast

Jimmy Kimmel dropped a major Dark Phoenix spoiler when the cast visited Jimmy Kimmel Live, clearly catching the assemblage of stars off guard.

"This is not a spoiler, but we know Jennifer's character Raven gets killed in this movie," Kimmel said of Jennifer Lawrence's blue-skinned team leader Mystique, whose accidental death at the hands of a cosmic force-possessed Jean Grey (Sophie Turner) fractures the X-Men.

Nicholas Hoult, who plays Beast, is clearly surprised by the admission. And franchise newcomer Jessica Chastain, who plays alien Vuk, appears to grimace.

"I was told not to say that," Turner said.

But Kimmel may be in the clear: early trailers hinted Mystique was going to die as far back as September, and writer-director Simon Kinberg openly acknowledged her death in a February interview with EW.

"Well, the thought process behind that was to primarily show that this is a movie that is unlike other X-Men movies," Kinberg said.

"It's a movie where shocking things happen, where intense, dramatic things happen. People don't just fall off buildings and dust themselves off and walk away. There's a reality to this movie and a consequence to this movie. Even more than that, it was to show that Jean/Dark Phoenix is genuinely a threat to everyone, including the X-Men."

Because Lawrence vowed only to return for her final X-Men film if first-time director Kinberg steered the project, the longtime franchise writer-producer "had a lot of emotions about it."

"I was obviously sad about it, as Jen's friend, and also as a fan of Jen as an actress. But I felt it was the strongest, most dramatic thing for the movie, and sometimes you have to make those kinds of hard decisions to service the larger story," Kinberg said.

"And the larger story really is Jean cracking up, losing control because she's more powerful than anyone else in the world. To dramatize that properly, you have to show real loss, you have to show real pain and show real threat and menace. I didn't want to do that by her blowing up a building with anonymous people in it. It had to feel really personal for the X-Men, and I wanted it to be something that would fracture the X-Men as well. Mystique is someone who in our universe has been part of the X-Men and has been part of Magneto's world. Her death impacts literally everybody."

Dark Phoenix is now playing.