Detective Dinosaur and Officer Pterodactyl are challenged to solve three cases when a hat is missing, a shoe squeaks, and a loud clanging comes from a dark alley at night.
Even though summer vacation starts in five days, Pearl and Wagner, a rabbit and a mouse who are best friends, worry about next year's teacher, mean Ms. Bean.
April Fools' Day is not a happy one for Wagner the mouse because his best friend, Pearl the rabbit, and other children and adults at school keep tricking him.