After a long journey in your small rowboat, you arrive at Neptune Island, set on repairing the light atop the lighthouse. However, a series of puzzles designed to deter intruders stand in your way, each one growing more desperate as you get closer to restoring power to the light. With only a weak lantern to guide you through the darkness, you must navigate the lighthouse's challenges, and ensure the safety of sailors in the surrounding fog. Along the way, you'll uncover the strange phenomena that make Neptune Island unlike any other.