Campion returns to Pontisbright in disguise in order to track down Savanke.

Campion searches for the crown of a lost kingdom. Campion is asked to find documents that will prove that the Frittons are the rightful owners of a tiny Dalmatian state where oil has been discovered.

Influenced by his feelings for Linda Sutane, Campion refuses to believe the evidence against her husband Jimmy, and continues trying to clear his name. But when another murder occurs, Sutane's innocence becomes impossible to sustain.

Campion is determined to prove the innocence of his friend Mike Barnabas, arrested for the murder of Paul Brande, but in trying to do so he puts his own life in jeopardy.