Occasionally, the rugged landscape of Scotland attracts dreamers who move north, wrapped in fantasies of enjoying the simple life. They usually don't last, defeated by the climate or by inhospitable locals. But it looks as if Effie Garrand has come to stay.

When local constable Hamish Macbeth calls on her, he is amazed to find the small woman still in residence after a particularly hideous winter. Unfortunately, Effie is also quite delusional, having convinced herself—and everyone else—that local artist Jock Fleming is in love with her and that they are engaged.

After a huge fight with Jock, Effie is found in the mountains, dead from poisoning. Now, it's up to Hamish to find the dreamer's killer—before any more nightmares unfold.