When Brett's skateboarding abilities dramatically and inexplicably improve after using the Lizard, a skateboard mysteriously unearthed in his front yard, his friends start to wonder if the skateboard is haunted.
Fifth-grader Cam uses her photographic memory, with help from her friend Eric and his twin sisters, to solve the mystery of Poochie, a famous canine television star.
When a Roman widow shows unusual interest in Flavia's father, Flavia decides to discover Cartila's true motives by performing twelve tasks, just like the Greek hero Hercules.
Suspecting their friend Jonathan is alive, Flavia, Nubia, and Lupus go to Rome for the Colosseum Games, facing wild beasts, criminals, conspirators, and gladiators, and where Nubia is called upon to make a terrible choice.