Months after Inara leaves Serenity, Mal finally learns a shocking reason: her companion is dying of cancer, and there is very little time left. The crew is desperate for information that might help. Oncologist expert Eso Wen is said to have developed the treatment but was discredited and sentenced to life imprisonment. He is rumored to be on Atata, the notorious prison planet of the Alliance. The prisoners there are unguarded and survive as best they can. Moreover, the terraforming of the planet has not been completed, so the world is a frozen wasteland inhabited by brutal mutants. To save Inara, the Serenity team will have to once again do the impossible...