Mystery Tales is a book containing five thrilling and mysterious stories. In the first story, Dahlia and her friend Orion follow the clues of a note to find a hidden treasure in the forest, but they are not the only ones looking for it. In the second story, Jasper and Lyra find a mysterious old box that leads them to discover a hidden family heirloom stolen by a suspicious neighbor who turns out to be Jasper's estranged aunt. In the third story, Ava and Finn investigate the disappearance of a valuable museum artifact, only to find out that the curator had stolen it himself. The fourth story, The Case of the Missing Magnifying Glass, follows siblings Niamh and Orion as they try to solve the mystery of why things keep going missing in their neighborhood. Finally, the fifth story tells the tale of a young girl who finds a magical book that takes her on a mysterious and fantastical adventure.