"X Men: First Class" is a film that focuses more on the development of its characters than in the development of any plot. The story starts when our two main characters, Professor X and Magneto, are forced by a rogue government organization called The United States government to compete for the rights to use a mysterious telepathic device called the "Bolt." The Bolt has the power to control the minds of anyone who wears it. If it is used to kill someone, however, then the user would be turned into a "Bolt zombie," living an entirely miserable life under a series of unending nightmares. The Bolts, however, are a highly sought after possession, so only the most gifted students are allowed to wear them.
With the release of "X Men: First Class," the new series of X Men takes a much bolder approach to its characters and plot. For example, Magneto's father was a Nazi sympathizer. When Magneto was young, he was taken away from his mother and his father and raised as his own. He was not allowed to speak or read. When Magneto discovered that the Nazis were responsible for his father's death, he took a great dislike to his father, who was also known as a Holocaust survivor and took an instant dislike to Magneto as well. The X Men soon came into contact with the Nazis and Magneto learned of his father's past and his own history in the X-Men comic book. As such, he grew to hate and despise the people around him, especially those that worked in the X-Men.
Professor X has an even greater dislike for those who are not of a different race. This may be a reason why Professor X feels so drawn to Mystique. Mystique grew up on a Native American reservation in North Dakota, where she was abused by the tribe members as a child. She grew to hate all of them and eventually developed a hatred of herself for all of the X Men as well. Professor X took a shine to her as well, although this may have been a result of jealousy. because he felt she had grown to love him and be completely devoted to him.