After stepping into a ghost circle Thorn is urged to locate the Crown of Horns, and sets off on a quest with Fone Bone to traipse through the sacred grounds of dragons, with the hope of returning with the only thing that can save everyone and everything she holds dear.

Series order: 1."Out from Boneville" -- 2."The great cow race" -- 3."Eyes of the storm" -- 4."The dragonslayer" -- 5."Rock jaw; master of the Eastern border" -- 6."Old man's cave" -- 7."Ghost circles" -- 8."Treasure hunters" -- 9."Crown of horns".