Niko and his friends have a funny feeling about their new substitute teacher. First Mr Reynolds asks their classmates to use their unique superpowers to practise breaking into a safe. Then an online mug shot seems to show a striking resemblance between Mr Reynolds and a criminal kingpin. Is Mr Reynolds really a supervillain in disguise? And if he is, how can Niko and his friends foil the super-sneaky substitute's evil plans? Young readers will find out in this fun and funny chapter book bursting with colourful comic book-style illustrations.