What do you do when you learn that MacDougal, the world's most notorious criminal mastermind has taken up trumpet lessons? You investigate, of course!
Meatloaf who lives with MacDougal and pretends to be an ordinary cat visits Caitlin and Rio to ask for their help. MacDougal has become increasingly unstable ever since he lost his shadow to the Coyotes. Why is MacDougal taking up trumpet lessons? What is he doing in his secret lab? And why does he have the plans of the City Art Museum? Could it have something to do with the traveling King Tut's Exhibition that has come to town?
The friends must solve the puzzle and still navigate events involving people oblivious to the dangers of MacDougal's plans. There is Mrs. Brewster who wants to exterminate all the coyotes - which would put the shapeshifters at risk. Caitlin feels sorry for her archnemesis, Hettie Bigby, because her parents are getting a divorce after Hettie's mom ran off with an inflatable Santa at the Annual Holiday Bigby Party. Of course, Hettie blames Caitlin. Caitlin has so many secrets to keep it makes her head hurt. Then there is the class project with the theme of Ancient Egyptians- Molly wants them all to dress up and wear make-up. And when things can't get any more fraught, someone gives Caitlin a Valentine's Day card. Everyone knows that Valentine's Day makes sensible people completely silly.
As Rio and friends uncover more of MacDougal's plans it puts them in danger - when a plan to rescue animals captured by MacDougal to experiment on in his secret lab goes horribly awry, Caitlin's parents make Caitlin promise to stay out of it. But how can they when Meatloaf is risking his life by pretending to be an ordinary cat? And when they learn the reason why MacDougal wants King Tut's trumpet Caitlin, Rio and their friends realize that they must tell lies and break promises. MacDougal must be stopped at all costs.
In the final confrontation, Rio and friends realize the importance of friendship and teamwork. They are stronger together.
No more lies. No more secrets. Only the truth.
