When an alien substance is absorbed into Jean Grey in space, she faces her dark side, turning against all who befriended her.

Very weak. I didn't like the alien angle at all, and Jean Grey just turned whiney, or had her stern face from Game of Thrones. After this marathon, I have no intention of revisiting this movie.

I like most of the X-Men movies, and this one, like the others, was well-made, and enjoyable. They killed off a major character, but it served to highlight to Jean how far toward darkness she'd gone. She still fought for good, just not in the way the others wanted her to. Professor X took too much blame here, but it shows how secrets decades old can still hurt. I didn't like the alien angle, and it seemed like a very ineffient way to repopulate a species. Fortunately, they were short-lived thanks to Jean.