The Mystery of the Invisible Thief (Five Find-Outers #8)

Who is the large footed thief committing the robberies in Peterswood? He leaves his footprints and people have heard his cough, but he appears to be invisible! Mr Goon is eager to solve this mystery, and put his disguising skills to the test, which he'd learned from a refresher course. The Find-Outers are also on the case, with Fatty using his own disguising skills to outwit Mr Goon. So who is going to solve this mystery first, the Find-Outers or Mr Goon.