The Factory on the Cliff begins with a spoilt golf holiday at a coastal golflinks hotel in Aberdeenshire. 'George Templeton's car refused to start on the self-starter. He jumped out impatiently and gave the handle a mighty twist. The engine backfired and dislocated his thumb and he found himself unable to play golf for the remainder of his holiday.' Unable to play golf with his friends, he resorts to country walks and stumbles upon suspicious goings-on at a cliff-top farmstead where there are numerous outbuildings. The story moves from Scotland to London, and then to a small village in the Home Counties. In a fast-moving thriller which in some degree resembles John Buchan's The Thirty-Nine Steps, George Templeton and his friends must foil an international plot to mass-poison many countries in the World.

Macdonell uses his usual skill, well-dosed with ingenious twists, and a fast moving story-line, to keep the reader riveted to the book. Chase, conspiracy, espionage, quick-thinking initiative and much adventure with Irishmen and Russians thrown in, keeps the adventure in a high gear from beginning to end.