With winter setting in and the Frozen Pass closed, everyone except Dag and Calder are trapped on the Pale Sea. Including Strongrock pirates.

When the pirates attack the warehouse where Pia and her sister have taken refuge, the small group is able to fight back. Pirate prisoner in tow, Pia makes her way to Lavais Port, where she meets up with Gustav, who is on a dangerous mission of his own and needs a partner. Keeping people safe—keeping her sister safe—means that Pia must make a choice and become what she swore she wouldn't: a true Intelligencer.

And while Dag continues the vital task of shipping supplies through the Teeth, Calder remains in the Sapphire Sea to stop an assassin from killing Charis and Inger, who are on the run from both the assassin and the corrupt Messanos Council. An unlikely and unpredictable alliance with pirates ends when their ship is captured, setting Calder and his sister ashore in dangerous waters with time running out. Can Luck save them this time?