Gil Cunningham and an old acquaintance, Glasgow merchant Augie Morison, report the gruesome find of a severed head instead of an expected delivery of books. At the inquest, Morison is accused of murder and imprisoned. He appeals to Gil, who sets out to identify the dead man and establish the provenance of the treasure that lay beside him. The trail leads from the court of James IV at Stirling via a cooper's yard in Linlithgow, to another murder on the bare slopes of the Pentland Hills.