"Sunless Sea" is a survival and exploration game set in a dark, underwater world known as the Zee. Players take on the role of a ship captain navigating this mysterious environment, where they must manage resources, crew morale, and the dangers lurking in the depths. The game features a rich narrative, with various quests and encounters that unfold as players explore. The game is set in the same universe as Fallen London, a text-based game filled with unique characters and stories. Players can choose different ships and customize their journeys, encountering strange creatures and factions while uncovering the secrets of the Zee.