Rising Storm is the fourth book in the Warriors series, written by Cherith Baldry and Kate Cary under the pen name of Erin Hunter. The series follows the adventures of four Clans of wild cats. In the previous book, Forest of Secrets, Graystripe's mate, Silverstream, died while giving birth. ThunderClan and RiverClan fought over the two kits. Graystripe decided to join RiverClan, despite knowing he will be shunned there. In Rising Storm, Fireheart has to tackle his new duties as deputy, knowing that the old one, Tigerclaw, who had been exiled, is out in the forest somewhere. At the end of the book, Tigerclaw becomes leader of ShadowClan and receives the name Tigerstar. The main theme in the book is power. The forest in the book is inspired by multiple natural locations.