This two-in-one book features Tatiana and Nicole, two ten year old girls who often find themselves solving mysteries. In the first book, The Case of the Missing Diamond, in the middle of a wedding between the cat and a stuffed bear, a precious, borrowed gem suddenly and mysteriously disappears. In the second book, The Case of the Strange Lady, a cry in the woods and a mysteriously appearing, then disappearing young girl send Tatiana and Nicole searching for answers!