Persuaded by Polly Duncan, his beloved companion, to join her in a group tour of Scotland, Qwill expects to revel in his Scottish heritage while keeping Polly safe from the Pickax Prowler. Instead, his trip is cut short when a thief swipes a suitcase, the bus driver disappears, and a fellow tourist is found dead—all in the same day.

Although the town of Pickax is in a tizzy over the recent events, Qwill has other, more puzzling worries on his mind: Who is the fellow still following Polly? Why is Koko licking Qwill's photographs of Scotland and tackling him on the apple barn stairs? Upon investigating the secret life of the deceased and the bizarre behavior of one of the tour's members, Qwill's sensitive moustache tells him one thing: more trouble is on the way.