The elders in Stretomorozsk tell tales of a cove beyond the rocky cape, where the shore drops into dark depths — a place best left alone. They call it the Dark Cove. Its waters never freeze, even in the bitterest cold, as if the sea itself breathes warmth from underground veins. Strange, lingering melodies sometimes drift from the mist above the water, and any fisherman who strayed there returned with grey temples and empty nets.

Beneath these unfrozen waters lies a submerged city — the vast domain of the Tsaritsa, supreme ruler of the sea folk. Merfolk are no myth. They live by ancient ways, guard their mysteries, and obey strict laws.

At the Tsaritsa's court, Mitya serves as the lead scientist of the Royal Energy Commission — a guild that studies geothermal sources, deep-sea currents, and bioluminescence to provide heat and power to the underwater city. Mitya is a true genius with a phenomenal analytical mind. For his age, he has studied more ancient lore and human customs than any elder. Yet he treats dry routine and archives with casual disregard. He is a passionate experimenter, willing to challenge tradition in the name of science. Instead of staying in the deep-sea grottos, he constantly escapes to the surface, to the Dark Cove, to secretly observe humans — their lives, their speech, their habits.