Fire and Ice is a children's fantasy novel, the second book in the Warriors series, written by Kate Cary under the pen name of Erin Hunter. The plot centers around Fireheart and Graystripe, newly promoted warriors of ThunderClan, which is one of the four groups of feral cats living in the wilderness. Fireheart learns that his best friend Graystripe has fallen in love with Silverstream, a warrior from RiverClan, even though it is against the cats' "warrior code".
The book was first published on June 1, 2003 in the US as a hardcover. Since then, Fire and Ice has been released in paperback and e-book format in other languages. The main theme of the book is that the type of person one is inside is more important than the way one seems from the outside. The book received mixed reviews: the negative reviews criticized the flat characters, and how troublesome it was to flip back to the characters list due to the large number of cats; positive reviews praised the suspense and rising tensions in the book.
Fire and Ice takes place in a fictional forest which is home to four Clans of wild cats, ThunderClan, RiverClan, ShadowClan and WindClan, each of which lives in a territory best suited to their skills. The authors based the forest on New Forest in southern England.
• Fireheart is the main protagonist of the book. Originally a house cat named Rusty, he left his human owners to become an apprentice in ThunderClan. He is sent with Graystripe to find WindClan, who were chased out of their home by ShadowClan. Later, he realizes that Graystripe is in love with Silverstream, a warrior in RiverClan. Although he advises Graystripe against meeting her secretly, Fireheart agrees to keep it a secret.
• Graystripe is Fireheart's best friend. After receiving his warrior name, Graystripe is sent with Fireheart to find WindClan, who were chased out of their home by ShadowClan. During a patrol, Graystripe is saved by Silverstream, a RiverClan warrior, when he falls into the river, and almost drowns. As a result, Graystripe and Silverstream fall in love and begin to meet each other in secret, against Fireheart's warnings.
• Silverstream is a RiverClan warrior and the daughter of RiverClan's leader, Crookedstar. After saving Graystripe from drowning in the river, the two fall in love. Since the warrior code forbids cats from different Clans to be in love, they begin to meet in secret, sneaking out of camp in order to see each other.
• Tigerclaw is the main antagonist. Tigerclaw had previously killed his own Clanmate, Redtail, in hope of taking Redtail's place as deputy. Instead, Lionheart becomes deputy, but he too, later dies. Tigerclaw then finally becomes deputy. Only Fireheart, Graystripe and Ravenpaw know of Tigerclaw's plans, but they do not tell anyone out of fear of him.
Fire and Ice begins with Fireheart and Graystripe performing a traditional silent vigil after their promotion to warrior status in Into the Wild. As their first task as warriors, Fireheart and Graystripe are assigned to find and bring back WindClan, which had been driven out by ShadowClan, and bring them home. They succeed, finding WindClan under a tangle of Thunderpaths (probably a highway interchange), and bring them home.
Soon after, Bluestar apprentices Cinderpaw to Fireheart, and Brackenpaw to Graystripe. During a hunting patrol, Graystripe almost drowns after chasing a vole onto thin ice, falling in the river separating RiverClan and ThunderClan, but is rescued by Silverstream, a RiverClan warrior. Graystripe and Silverstream fall in love; however, this is against the warrior code, a code of honor that all warriors must follow. Fireheart discovers their relationship, and unsuccessfully attempts to discourage them from seeing each other. Graystripe finally agrees to meet Silverstream only at the full moon at the Gathering, when the four Clans meet to share news. Fireheart, later realizes that Graystripe has not been keeping his promise. Because Graystripe is often gone to see Silverstream, Fireheart takes over training of Brackenpaw, as well as training his own apprentice.
Tigerclaw, in his ambition to become leader, sets a trap for Bluestar by the Thunderpath (road), intending to kill her, thus bringing him closer to becoming leader. Instead, Cinderpaw is crippled by the trap. Her leg is broken, and when it heals, she has a permanent limp, preventing her from becoming a warrior. She then trains under Yellowfang to become a medicine cat.
Fireheart is reunited with his sister, Princess, a kittypet living in a Twolegplace (a human town). Princess gives Fireheart her oldest kit, Cloudkit, to take into the Clan as a new apprentice. Although Fireheart agrees to accept the kit, his Clanmates, with the exception of Frostfur and Graystripe, are reluctant to accept him because of his kittypet blood. Bluestar allows him to stay, and Brindleface becomes his foster mother.
Brokenstar, the former ShadowClan leader, eventually attacks ThunderClan, along with several other exiled ShadowClan warriors. After the battle, the rogues are driven off, with the exception of Brokenstar himself, who is blinded by Yellowfang and is kept as a prisoner. When Fireheart suggested to kill the evil cat, Yellowfang refused, sadly revealing that herself is Brokenstar's mother.
Later, ThunderClan becomes involved in a fight against RiverClan and ShadowClan when RiverClan and ShadowClan unites and tries to drive WindClan out again, and WindClan allies themselves with ThunderClan. When Fireheart is attacked byLeopardfur, the RiverClan deputy, Tigerclaw watches as Leopardfur and Fireheart fight, and does not attempt to help Fireheart. Silverstream attacks Fireheart but releases him; he attacks her but sees Graystripe's look of dismay, and releases her.Darkstripe witnesses the event and reports it to Tigerclaw. Consequently, Fireheart becomes certain that Tigerclaw is not to be trusted.
The main theme of Fire and Ice is that "it doesn't matter where you come from, only who you are inside". Fireheart is challenged by other cats because he was once a kittypet (house cat), despite having proven his loyalty and bravery as a warrior. Similarly, Cloudkit was initially not accepted by the Clan because he had kittypet parents. Other themes include loyalty, betrayal, and forbidden love.