In Origin, Pia is immortal, and she grew up in a secret compound in the rainforest with a group of scientists who are creating an immortal race. Pia's goal in life is to learn the secret to her immortality, which the scientists will tell her when she is old enough to run the experiment. But that all changes when she escapes and meet Eio, a boy who lives in a nearby village. She continues to sneaks out and he teaches her about the outside world. Together, they learn the real reason behind the experiment, and why it might not be as good as it seems.