This is a pure fair-play mystery, grounded entirely in the rigorous logic of reality. With every clue and unusual detail laid before the reader, follow investigator Arthur Crow into a storm of logic-driven deduction.

Set in a gloomy metropolis buried under a relentless downpour, the story unfolds with a tense, rain-soaked atmosphere as Crow, armed with his iconic black umbrella, cuts through the city's lies alongside the exhausted Captain Reed.

Through the relics left behind by Eli Morris, a decade-old secret collides with a series of impossible crimes. Beneath the surface of an ordinary routine, a hidden design gradually comes into focus—leading to a battle of wits, contradictions, and truths concealed in plain sight.