When Herbert Terrell falls off a mountain in Czechoslovakia, accidental death seems the inevitable verdict. But his step-daughter, Tossa, does not bow to the inevitable. She was going to Europe anyway, and finds it easy to persuade her companions to make a minor detour to the mountain.
Bewitched by Tossa's brown eyes, Dominic Felse is game for a change of plan, though he doesn't at first suspect her real motive. And he's certainly not prepared for their innocent touring holiday to become a deadly game of cat and mouse.
A fragment of an English folk song, the plaintive lament of a pipe, an unexpected corpse - these are the clues that the amateur sleuths must solve to discover the riddle of the piper on the mountain.