West Dean is shaken by a new incident. While the surrealist artists begin to suspect each other, Scotland Yard's investigation focuses on a single guest. Paranoia spreads, secrets unravel, and new facts about Sheila's past emerge.

New guests arrive in West Dean, bringing added tension. While Quant and Thistlethwaite try to put the finishing touches on things, a masked figure emerges from the shadows. Is it a warning, or something far more dangerous?