A positive crimewave has descended on Miss Seeton's peaceful home village of Plummergen. There's the Sherry Gang, who go round offering to help old folk with their shopping then ply them with drugged booze and rob them. And a return to olden times with the Dick Turpin robberies - coaches of people held up on the highway and told to "Stand and deliver!"

When the Battling Brolly tries to help the police by creating some of her famous sketches she seems to hint at a connection between the gangs - but what? If only Chief Superintendent Delphick can work out the subconscious clue behind Miss Ess's cryptic cartoons.

Serene amidst every kind of skullduggery, this eccentric English spinster steps in where Scotland Yard stumbles, armed with nothing more than her sketchpad and umbrella!