Geronimo Stilton, a little mouse journalist, is in the process of finishing up with all his chores one fine evening. This is when he opens the letter that he had received from his Uncle Stingysnout. In the letter, Geronimo's uncle gives him an urgent message. The letter tells him that Stingysnout needs to see his nephew as soon as possible, if possible immediately. It makes Geronimo happy to think that he will be seeing his uncle again and so, without wasting any time, the small mouse heads straight to Penny Pincher Castle. But what does little Geronimo find? Instead of spending a pleasurable vacation, his old uncle Stingysnout has invited him to put him to some boring work. It is turning out to be a stinky vacation for Geronimo.