29 books • 7 series
Book #1: The City of Ember
Book #2: People of Sparks
Book #3: The Prophet of Yonwood
Book #4: Diamond of Darkhold
Book #4: Voyagers: Infinity Riders (Book 4)
Book #5: Voyagers: Escape the Vortex (Book 5)
Book #5: Voyagers Escape The Vortex (Book 5)