Misterio de Los Mensajes Sorprendentes / the Mystery of the Strange Messages

Mr. Goon, the policeman, can't understand it. Messages keep coming to him, popping up all over the place. But who is sending them? He thinks it is Fatty, playing tricks on him but this is the first the Five Find-Outers have heard about the messages. It all becomes a remarkable mystery, and one which the Five just have to solve.