A tale of friendship, betrayal, and forbidden love—set against the backdrop of Edo’s criminal underworld. While patrolling the Honjo district, the legendary samurai detective Heizo Hasegawa crosses paths with his old dojo friend, Samanosuke Kishii, and a local ruffian, Hikoju of Sagami. When they discover that Ofusa, the woman they both once loved, has been forced into marriage with a corrupt lord, their reunion takes a dark turn. As secrets from their past resurface, a deeper conspiracy tied to their former mentor begins to unravel—one that will test Heizo’s loyalty, honor, and sense of justice.