Getting refreshed after a long Winter, Holmes and Watson relax at a seaside village. The setting is still pretty bleak, and superstitions run rampant about the bluffs where the waves crash, and cause mist to rise high. It doesn’t take long for a report of murder to land at the doorstep of Sherlock Holmes.
The crime scene, and surrounding events serve to play into the superstitions that the devil himself is behind the deaths. Even the local vicar is beginning to believe the devil has a hand in it.
Revisiting the crime scene, Holmes discovers what he claims holds the answer to the mystery. First, he conducts an experiment of the poison on himself, attended by Dr Watson. The poison is stronger than Holmes thought, but as he takes action to clear the room, the real killer is identified. Justice is done, but it isn’t 2quite carried out in the conventional manner.