In the tenth A to Z Mysteries super edition, Dink, Josh, and Ruth Rose have a sleepover . . . with a Spinosaurus! It's sleepover night at a science museum in Boston. Dink, Josh, and Ruth Rose can't wait to settle their sleeping bags near the museum's colossal fossil—a giant Spinosaurus skeleton—and tour the exhibits long after closing time. But after they fall asleep, they wake to a terrible crash! Is the dinosaur fossil damaged? Or is there another big problem at the science museum? Help Dink, Josh, and Ruth Rose solve mysteries from A to Z! From The Absent Author to The Zombie Zone, there's a mystery for every letter of the alphabet, plus ten super editions with even more A to Z fun. And don't miss Ron Roy's series for younger readers, Calendar Mysteries!