Chloé, an archivist and bibliographer living on the shores of northwestern France, has her curiosity piqued after finding a strange and ancient manuscript in her family home.
A longtime victim of her husband’s violent beatings, one day Chloé shoots him and flees by boat to the Scandinavian island of Heldenskøn. This is where her father, a famous yet mysterious author, was born and raised. On this isolated island, she discovers a remote monastery and settles into a seemingly cozy pension run by Grégoire, an enigmatic professor.
At first, she feels safe with this new life in a new town. But soon doubt hangs over her like a heavy cloud, and sleepless nights drive her to find out more about the old manuscript. The ancient book recounts the tale of a secret society of mute women living underground for centuries, right there on the island. They’ve been tasked with guarding humanity’s knowledge and secrets for all of eternity.
Does such a society exist? What if the manuscript wanted Chloé to take it back to where it belongs? And… why is Grégoire so interested in the book?