In the distant future, mankind attains longevity through gene manipulation, but the compensation is the loss of natural reproduction. Meanwhile, their clones, who rebelled 1,600 years ago and now rule the bottomless underworld, seem to have become fertile. The government sees this as hope to rescue mankind from extinction and sends civilians in to carry out an ecological study. Seven years in the making, director Takahide Hori's solo tour de force – from puppet sculpting to scoring – has been praised by Guillermo del Toro as a "work of deranged brilliance", crafting a stop-motion masterpiece that evokes H.R. Giger's dark imagination.