"Who Stole the Zmulobeast?" is a humorous detective story for middle school-aged children. The story introduces the Pi in the Sky Squad, a crew of (mostly) kid detectives comprised of a talking dog with a wise-cracking sense of humor, a hovering space alien from the Planet Acabagua, a rambunctious collection of exceptionally curious youngsters, and Chief, the poor adult tasked with supervising this bunch. In this, their first adventure, the Pi Squad must find out who stole a creature known as a Zmulobeast - just as soon as they can figure out what a Zmulobeast is.