Space Symphony Maetel: Galaxy Express Side Story is an OVA series spin-off of Galaxy Express 999. It tells the story of Maetel after the events of Maetel Legend and before Galaxy Express.
Synopsis[]
After escaping the ill fate of La Metal, Maetel had wished for a chance of peace between the Machine Empire and humans. Queen Promethium herself seems to have agreed to this and even gave Maetel to offer as the new queen. However, when the actions of a boy named Nazca cause a disturbance reveal Promethium's hidden agenda of domination, a civil war breaks out among the denizens. Maetel against all odds only wants peace and co-existence between the people, but acknowledges that she cannot do so as queen lest she becomes Promethium's puppet. Because of this, Maetel is forced to fight her mother to remove her from power, even if it seems hopeless.