Zorya Ashwood has loved her commander in silence for three years. She has run from the same nightmare for twenty. Amber light. A voice calling her name. A world she was always told does not exist.

When the Halcyon Wake is sent to find a missing scout ship, Zorya expects a routine search. She does not expect their course to lead straight into the one name she has never spoken out loud. Thule, Officially a myth. Unofficially, a graveyard that has been swallowing Fleet ships for generations, and theirs is next.

Stranded after a brutal crash, Zorya and her crew find a forest that should not exist, ruins carved with a language she somehow already knows, and a village of pale, altered strangers offering shelter no one should trust. In the middle of all of it, Commander Rurik Sable finally reaches for her hand and does not let go.

But Thule never gives without taking first. Her crewmates begin to change, slowly losing themselves to something ancient in the soil and the water. The only way home is a gate hidden deep in the mountains, and it opens for six days every hundred years. The countdown has already started.

Then Rurik confesses the truth he has carried since before the mission began, a secret order that could have cost every one of them everything. Before Zorya can decide whether she can still trust him, a stranger steps out of the trees. Pale. Silent. Utterly changed. Her father, twenty years after she watched him disappear.

Now she has days, not months, to choose between the father she never stopped grieving and the man she is not sure she can still trust, while a door to the only way home ticks steadily toward closed.

Will Zorya find a way to save them both before Thule decides for her?