Mr. Cheeters is Missing

When the eccentric Blanche Porter reports that her beloved Mr. Cheeters has vanished, it isn't your standard missing persons case. As Nancy Drew soon discovers, Mr. Cheeters, is a pet chimp. Or is he? Based on a preliminary investigation and information obtained from Blanche's brother, Lawrence, the River Heights police dismiss the case as bogus - doubting that there ever was a Mr. Cheeters to begin with. But when Nancy Drew discovers there's a missing diamond necklace as well - she's on the case! Can Nancy, along with Bess and George, recover the great ape and the necklace, or has Blanche Porter made a monkey out of Nancy Drew?