Atom rescues Bem, a robot soldier who has escaped from a rubbish planet floating in space and is on the brink of death. A warm friendship develops between Atom and Bem, and it continues to grow. But one day, the rubbish planet suddenly begins to approach Earth. There is only one way to avoid a collision with Earth. Only this is... What will Astro do? Will he be able to protect a peaceful Earth as well as his friendship with Bem?