Synopsis: The book starts off in a Friday afternoon, with Josh, Dink and Ruth Rose having lunch in Ruth Rose's backyard. Dink and Ruth Rose convince Josh to come with them to the Penelope Gwinn concert dressed as a penguin. At the concert they notice Penelope wearing a diamond penguin pendant around her chain. After Penelope sings for a while, there is an intermission, where the three friends buy some hot dogs and decide to ride a carousel. While they are riding the carousel, Dink hears yelling from over the stage, and when he tries to find out what the commotion is about, he falls down and hurts himself. They find out that Penelope Gwinn got robbed by someone stealing her diamond pendant. Dink goes to the First Aid tent where he is tended by Dr. Fleming, who puts a bandage on Dink's arm and takes him to the hospital to get it x-rayed.
As all the audience members were wearing penguin masks that was provided at the entrance, Penelope did not get a chance to see the culprit's face as he took the pendant from her. Dink, Josh and Ruth Rose suspect a few people who could have taken the pendant, such as Frank, the hot dog vendor who was in a hurry to leave his stall to get Penelope's autograph, or the woman who was sitting in front of Dink who got up as soon as the intermission started to get Penelope's autograph. Little to the gang realize that Dink's x-ray holds a big clue to their solving the mystery.
Review: I thought this was fun book to read. There are a lot of suspects added to the book, so it was interesting to find out who the thief was and how they planned it. At first, I thought the two stories, of one of the stolen diamond, and the other of Dink's accident, would be unrelated to one another, but I enjoyed how the author brought these two stories together.I also like how the author added new words like `purloined' into the story for young readers to learn.
Some of the parts which I enjoyed were when Dink and Ruth Rose convince Josh to go to the concert, when they see Hans going into the jewelry store, and when they realize who the culprit is.
There illustrations were also very nicely drawn by John Steven Gurney, and I liked the ones where the group goes to the concert and everyone is wearing penguin masks, and when they are all riding the carousel.
Overall, I thought this was a very nicely written book to the series, and I would recommend it to anyone who likes reading a good mystery book.