Cilydd's wife Goleuddydd, who is nine months pregnant, seems to vanish into thin air at a supermarket one wintry afternoon. Cilydd convinces his cousin, Arthur—a private eye who has never solved a single case—to help him with the investigation. So begins a tale of intrigue and confusion that concludes with a wild boar chase and a dangerous journey to the House of the Missing. Transforming a medieval Welsh Arthurian myth into a 21st-century quest, this is a lyrical look at love, grief, and father–son relationships set in a land that is at once contemporary and mystical.