In a distant future, where humans have reached the stars, we meet a young man named Tetsuro, who lives in a world where humanity has become almost robotic. After losing his mother in a tragic accident, his life takes an unexpected turn when he decides to embark on a journey aboard a space train that travels through the galaxy. His goal: to find the mysterious planet where eternal life is promised, a place where people can become machines.
Tetsuro is joined by Maetel, an enigmatic woman who offers him help and guidance on his journey. As the train traverses different planets and stations, each stop reveals a new world with its unique challenges, where Tetsuro faces not only physical dangers but also ethical dilemmas about humanity and identity. Along the way, he encounters a variety of unforgettable characters, from fellow travelers with their own stories to adversaries who test his skills and determination.
Throughout the journey, Tetsuro learns valuable lessons about love, loss, and sacrifice, questioning whether he truly wishes to become one of those mechanical beings. With stunning animation and a deep reflection on the future of humanity, this epic tale invites the viewer to embark on an emotional journey that transcends time and space, exploring the essence of what it really means to be human.