London detectives DemiChat and Lord Flannery Beagle discover that a scientist has gone missing! He has left behind a trail of purple powder which makes Flannery sneeze his way across France into Italy. Will Scotland Yard Police Dog Jake and Detective Inspector Robert Cooper help or hinder their investigation? Why are gangs of Italian and Irish crooks double-crossing each other to get their hands on the formula for the purple powder? What is the secret formula and what is it for? How does Italian Police Inspector Alessandra Bambini become involved? Will the kidnap victim be freed? And what part does his sister play?
Demi relies on her feline intuition and wit – and the devoted help of Flannery and Jake – to keep Cooper and Bambini focussed on the case to save the kidnapped victim and stop the formula from getting into the wrong hands!