Nina and her twin sister Artemis are not exactly ordinary teenagers. It's hard to remain "ordinary" if you grew up under the Overwatch Council and attended classes that bear little resemblance to high school classes. The Watchers' mission is to mentor the Slayers, girls with the magical ability to fight dark forces. It is only thanks to their tireless work that ordinary people continue to live, even unaware of the existing threat. Nina knows that one day she will have to join the Council of Observers. However, a new, unexpected turn of fate radically changes her life. Now only one thing is clear to her: becoming the Chosen One is easy. Making a choice is much more difficult.