When oceanographer Mara Venn is sent to Europa Station to investigate a pattern of impossible seismic pulses beneath the moon’s ice, she expects a faulty sensor array, a corporate cover-up, or both. Instead, she finds a rhythm older than human language, repeating from an ocean no one has ever touched. Europa Station is already failing. Its heat wells are unstable, its crew is divided between scientific duty and survival, and Earth’s governments want the discovery buried until they can own it. As the pulses grow stronger, Mara begins to suspect they are not a natural phenomenon but a message. To reach the source, Mara must cross the ice, descend through a fracture into the dark ocean below, and decide whether humanity’s first contact should be treated as a miracle, a threat, or a confession.