Humans have made contact with aliens while exploring planet Mars. Now Earth is fighting a losing war against them who they now called the "BETA". The war is going so badly that even new trainees are being sent straight to the battlefield before completing their training. Yui Takamura, daughter of a renown family, is the last survivor...

Ichiro Inuyashiki is a 58 year old man with an uncaring family. One day he discovers he has a terminal illness and while hiding in the park crying, he is killed by an alien spaceship. Desperate to cover their tracks, the aliens made use of the only equipment they had aboard their ship, reconstructing him into a powerful battleandroid...

Sentan Island is caught in the middle of a warzone. Akiyuki looks like your everyday student rushing off to school when there is an air raid and the school bus he was on explodes. While trying to help a refugee he helped sneak onto the bus, he finds himself "Xam'd" - when a human is injected with a seed known as "Hiruko" transforming them...