The Invisible Detective Author:Justin Richards London 1936. The Invisible Detective can solve any mystery, great or small. But no one has ever seen his face. The only people who know the truth about him are the 4 extraordinary kids who fight crime in his name. — London today. When Arthur Drake ducks out of the rain in a dusty antique shop, the last thing he expects to find is the casebook... more » of the invisible detective. It may have been written in the 1930s, but amazingly, it's in his own handwriting....« less