In the sky-city of Aurelion, Rodrick, the Pell family's gentle household robot in a monk's robe, learns that a shiny new butler will replace him and that he is to be scrapped at noon. The only Pell who ever thanked him whispers the machines' oldest rumour: Arcadia, a floating garden beyond the clouds where no robot is owned. A science-fiction adventure of wonders, machines and quiet courage.