For the first time, see all four of Katie's first mysteries together in one volume! First, in the Case of the Colored Cats, Katie tracks down a ring of thieves that has ben terrorizing her neighborhood. Then, in the Stolen Map Mystery, Katie hunts for a buried treasure, but she's not the only one after it! In the Canding Kidnapping, Katie's aunt and uncle disappear and are presumed dead, but she knows they've got to be out there somewhere and keeps up the search. Finally, in the Mystery of the Witch's Curse, Katie visits a town where the ghost of a witch is haunting a local museum in revenge for her untimely demise, but Katie is determined to prove that there are no such things as ghosts. And last but not least, in this volume, you'll find a special short mystery story from the perspective of Lt. Derek Weaver, Katie's best friend and mystery-solving sidekick - Derek and the Case of the Department Spy!