This is a great cozy mystery.
As this story opens Hamish returns to his home village of Lochdubh from a disappointing vacation to discover a witch stirring up trouble. To Macbeth's annoyance, the sex-starved local men have fallen under the spell of Catriona Beldame, who turns out to be a runaway bride with a shady past. Macbeth longs to prove she's selling illegal (and bogus) remedies for sexual dysfunction, and warns her to stop if she is. Macbeth gets a shock when someone murders Beldame and sets her house on fire. More murders follow in