Shannon Messenger graduated from the USC School of Cinematic Arts, where she learned-among other things-that she liked watching movies much better than making them. She's studied art, screenwriting, and film production, but she realized her real passion was writing stories for children. She's the New York Times and USA TODAY bestselling author of the award-winning middle grade series, Keeper of the Lost Cities, as well as the Sky Fall series for young adults. Her books have been featured on multiple state reading lists, published in numerous countries, and translated into many different languages. She lives in Southern California with her family-and an embarrassing number of cats. Find her online at ShannonMessenger.com.

Celina Frenn grew up in Latin America, where she explored the rainforest, entertained her sisters with made-up superheroes, and hid her thick bottle-cap glasses from her mother s camera. After graduating with a bachelor s degree in English, Celina was determined to use what most people considered to be a useless degree and then shocked herself by succeeding. As a freelance writer and showrunner, she has worked with brands like My Little Pony, LEGO Star Wars, Thomas the Tank Engine, and more. She is also the author of forthcoming graphic novel Spy Grandma. Celina lives in California with her animator husband and growing family. She loves screaming at video games, devouring books, and collecting swords in large quantities-much like a dragon collecting treasure.