In the Kingdom of Ravka, mapmaker Alina Starkov joins a dangerous quest to sail into the Shadow Fold to find supplies for the First Army after her childhood friend, Mal, is drafted for the mission.
Alina is taken into custody by the Grisha General Kirigan, who hopes that her legendary power as a Sun Summoner might one day bring down the Shadow Fold. Meanwhile Kaz Brekker and his Dregs gang are given a chance to score a big job – if they can catch Alina – and Inej is given a difficult task.
After General Kirigan brings Alina before the king she joins the Grisha to begin her training by the Second Army. Elsewhere Kaz, Inej, and Jesper take a risky journey across the Fold.
While Kaz's gang hatches a plan to break into the Little Palace, Mal's unit is tasked with locating a mythical stag. Alina's training reaches a frustrating impasse after a visit to Baghra, the elder Grisha.
Kaz and the others infiltrate the palace in search of an opportunity to abduct the Sun Summoner, who is preparing to publicly showcase her powers to the kingdom. Alina allows herself to become closer to Kirigan, and Mal makes his way back to the capital.
As Alina makes her way out of East Ravka she is forced to strike out on her own, as Kirigan closes in on the Dregs gang. Elsewhere, the Heartrender Nina finds herself shipwrecked with her witch hunter captor.
Aleksander's terrifying history is revealed, as the armies of Ravka hunt the Grisha and seek to force him to submit to the King. Alina and Mal search the woods for the stag, but run afoul of the Second Army.
General Kirigan takes Alina into the Shadow Fold along with a skiff full of ambassadors from Ravka's neighbors, and a plan to assert his own dominance. While Kaz's gang considers their next move, Nina and Matthias are forced into a corner.