A chance discovery of a man's body in a woodland pond sets off a careful investigation that combines police work with scientific inquiry. The scientifically minded sleuth collects and analyses physical evidence, reconstructing a sequence of odd occurrences tied to Marion D'Arblay and members of the Bendelow household. The plot advances through conferences, startling finds, misadventures, and narrow escapes, each revealing new facets of motive and arrangement. The case is ultimately unraveled by systematic forensic deduction that connects scattered clues, explains deceptions, and exposes the truth behind the apparently inexplicable events.