Book One: Water is the first season of Avatar: The Last Airbender, an American animated television series created by Michael Dante DiMartino and Bryan Konietzko and produced by Nickelodeon Animation Studio. Season one aired from February 21 to December 2, 2005, and consisted of a total of 20 episodes. The series includes Zach Tyler Eisen, Mae Whitman, Jack DeSena, Dante Basco, Dee Bradley Baker, Mako Iwamatsu and Jason Isaacs as voice actors for the main character.