In this movie the cure is created. The cure get rid of a mutants powers. The Brother Hood wants to rid of the people who made it and the human beings that want them to take it. So, the X-Men come to protect the people that made the cure and all the human beings. Since the Brother Hood and the X-Men are for different things they fight for what they want. Jean Grey just joined the Brother Hood in this movie and she gets the power of the Phoenix that takes control of her. She is killed my Wolverine which he is foreced to do. Magneto got the cure because Beast hits him with it. Also, Rogue takes the cure but she isn't forced to do it.