With a narrative that shifts from character to character, The Sworn continues the saga of Tris Drayke, King of Margolan and summoner mage, and the Winter Kingdoms begun in The Chronicles of the Necromancer series. A new son complicates Tris' life, especially when no clear omens can be read at the birth. Will the boy be normal, a mage like his father, or sickly? Meanwhile, signs of unrest and a resurgence of those with dark powers coupled with plague and bad harvests bring more problems.

Jair Rothlandorn, heir to the throne of Dhasson, rejoins the Sworn and his wife, Talwyn, shaman of the Sworn who protect the barrows. The barrows shelter the Dread and the ancient spirits they hold. Jair and the Sworn encounter Durim Black Robes who practice blood magic to open the ancient barrows and seeksd to free those spirits and use them against the living.

Old legends talk of a War of Unmaking. The Durim want to bring back the worship of Shanthadura, the Destroyer, and chaos. Over time, Tris and his allies become aware of conspiracy that reaches across the Northern Seas and involves a dark summoner, at least as powerful as Tris. Traitors in all kingdoms align themselves with the Durim. The novel stops abruptly with Tris and his forces arrayed for an invasion from the sea.

Ghost, dimonns, shapeshifters (werewolves), vampires (they drink goat blood), mages, witches, and ghost whores offer plenty of scope for Martin's talents. Magic, battle, and vows come with a heavy price. An accomplished writer of high fantasy, she holds the reader's attention and keeps the pages turning. Kings die and warriors gain battle scars, but the focus remains on the lives and relationship of the characters. They support one another and fight to protect the innocent.

Martin originally developed an outline for some twenty books set in the Winter Kingdoms. The present series, The Fallen Kings Cycle includes The Sworn and The Dread (2011) so far with others to come.