“Close off the area!” Sano yelled at his troops.

They hurried to bar the gates at intersections. The boulevard was a tumult of Sano’s forces and the crazed soldiers colliding, blades flashing and bodies flailing, murderous yowls and spattering blood. As Sano rode into the melee, he feared this was only a taste of things to come.

It was dawn by the time Sano, Hirata, and the detectives separated the combatants, arrested them for disturbing the peace, and dispersed the crowd. Now a sun like a malevolent red beacon floated up from a sea of gray clouds over Edo Castle, looming on its hilltop above the city. At his mansion inside the official quarter of the castle, Sano sat in his private chambers. His wife Reiko cleaned a cut on his arm, where a sword had penetrated a joint in his sleeve guard. He wore his white under-kimono; his armor lay strewn on the tatami floor around him.

“You can’t keep trying to maintain order in the city by yourself,” Reiko said as she swabbed Sano’s bloody gash. Her delicate, beautiful features were somber. “One man can’t stand between two armies and survive for long.”

Sano winced at the pain. “I know.”

Servants’ voices drifted from the kitchen and grounds as morning stirred the estate to life. In the nursery, Sano and Reiko’s little son Masahiro chattered with the maids. Reiko sprinkled powdered geranium root on Sano’s wound to stop the bleeding, then applied honeysuckle ointment to prevent festering.

“While you were out last night, the finance minister came to see you,” Reiko said. “So did the captain of the palace guard.” These were two of Sano’s friends in the bakufu. “I don’t know why.”

“I can guess,” Sano said. “The minister, who has recently joined Chamberlain Yanagisawa’s faction, came to ask me to do the same. The captain, who has sworn allegiance to Lord Matsudaira, would like me to follow his example.”

Both factions were eager to recruit Sano because he was close to the shogun and could use his influence to further their cause; they also wanted Sano and his detectives, all expert fighters, on their side in the event of war.