Moebius and Basil are contacted by a mysterious Collector, a man of considerable wealth, who has a collection of rare and illegal antiquities – everything from dinosaur eggs to stolen paintings.  He wants to hire the two thieves to obtain an ancient holy relic for him:  The Stone of Destiny, rumored to have magical powers over life and death.  It has been hidden in a secret chamber inside an abandoned Scottish castle for centuries.  The Collector promises to pay them a small fortune if they bring him back the Stone.

Basil and Moebius travel to the isolated, eerie Scottish moors, thinking it will be a simple job.  What they don’t know is that the booby-trapped castle is haunted by the bloodthirsty ghost of a long-dead knight, who hungers to possess the living.  To make matters worse, rival mercenaries, who will kill anyone that gets in their way, are also seeking the Stone… and they aren’t entirely human either.  Moebius and Basil never believed in the supernatural before, but all that’s about to change…

Basil and Moebius have to fool meddling archeologists, escape from the mercenaries, save the girl, solve ancient riddles to find the Stone, and fight for their very lives against the ghost of the evil knight without losing their heads.