The Curse of the Demon Prince is set in the backdrop of a fantastical, alternate-history version of feudal Japan (called Shoto), where honor can be stolen and only returned when and if justice is served. Seven companions (a wizard, a shinobi, two warriors loyal to opposing kings, a peasant that is more than he seems, and a pair of boys from Humao, the Isle of the Dishonored) risk death as they trek across the land of Shoto, seeking a sacred altar. There they hope to perform a sacrifice that will stop a Celtic demon from destroying their island home. Six of them know the truth...and the seventh is the sacrifice.