Dusk, a solitary Aviar trapper who works the deadly island of Patji, rescues a company clerk named Vathi from his own traps after the rest of her scouting party is killed by an enormous deep-sea creature. She carries a stolen device from the enigmatic Ones Above that can map the location of every Aviar on an island, and when her company's larger version of the machine is activated aboard their ship that night, every bird on Patji screams in simultaneous distress and Dusk's companion Sak shows him piles of corpses. Dusk forces Vathi to lead him on a night crossing of the island to stop the machine before it is used again, fighting through deathants, nightmaws, and the jungle's many hazards, and the two of them reach the camp in time to destroy the device. As Dusk and Vathi part ways, he realises the world he has protected is already ending - the companies will return, the Ones Above want the Aviar for reasons no one fully understands, and his own secret discovery that mainlander birds can gain Aviar talents when raised on the Pantheon islands will change everything.