Cam Jansen and the Ghostly Mystery

How do you catch a ghost? Fifth-grade sleuth Cam Jansen is hot on the trail of a cleverly costumed robber. Everybody in line for the concert saw the person who stole the money from the ticket booth. But nobody can give the police a description, since he--or she--is disguised as a ghost! Leave it to Cam, with her quick wits and amazing photographic memory, to unmask the thief and put the "ghost" to rest.