Long after the Classic series, a scientist, Dr. Cain, finds a capsule.With this capsule is a journal. Realizing that the journal was written by Dr. Light, he reads it and learns that the capsule contains a new robot, MegaMan X. Upon reading the journal Dr. Cain discovers that the capsule should not be opened for 30 years after X's creation. Having already been 30 years, Cain opens the capsule reviving X.Cain discovers that he is more advanced than any current robot with the ability to think and choose to do what he wants.He had true AI. Cain uses Dr. Lights design and makes robots, or reploids, with the same ability of thinking that X has. Unfortunately, a virus takes control of many of these reploids and makes them go maverick, a state where they turn against humans and non-maverick reploids.One of the most powerful reploids, Sigma, is infected with this virus and begins to spread the virus even more. X sets out to save the earth and defeat Sigma and the eight maverick bosses.