“I’ll inform Governor Nagai about what’s happened,” Sano said. Retrieving his horse, he rode into town. Fatigue weighted his limbs; the old wound in his arm ached, as did his head when he thought of all he must do in the next two days: Force the truth out of Chief Ohira and the Deshima guards; pursue the murder’s Christian angle; and follow up on his interviews with Peony, Urabe, Kiyoshi, and Abbot Liu Yun, whose stories he needed witnesses to confirm or disprove. All this, with the threat of war hovering over him. And he must discipline Hirata, whose help he desperately needed but could not accept.

The sun’s fiery disk dropped below the horizon; the sky darkened from bruise-red to black. As Sano passed tumbledown houses and dark alleys, a sense of danger prickled his skin. At three hours till midnight, Nagasaki’s early rising fisherfolk had long ago retired. The only lights came from lanterns above neighborhood gates. The only pedestrians Sano saw were raffish-looking peasants and samurai. Wary of bandits and outlaws, he kept his hand ready to draw his sword. He forced his tired mind to stay alert and his horse to trot faster.

The road ascended the hills. At the top of an incline, Sano looked back to see how far he’d come. In the sky above the harbor floated a lopsided ivory moon whose radiance shimmered on the black water and defined the silhouettes of anchored ships. Darkness cloaked the waterfront, interrupted only by weak lights at the harbor patrol station and Deshima guardhouse. As Sano scanned the scene, his heartbeat suddenly accelerated.

Far out on the water, toward the eastern cliffs, a green light flashed rapidly five times. Then a flashing purple light took its place, followed by bursts of brilliant white. While Sano watched, the lights repeated their sequence, moving steadily toward Deshima.

Sano turned his horse and hurtled downhill. His meeting with Governor Nagai would have to wait. Here was a chance to investigate Nagasaki’s mysterious lights, and determine their role, if any, in Jan Spaen’s murder.

The twisting road led him on a roundabout path to the harbor. Sano looked across the water and saw the lights flashing from a point halfway to Deshima. He passed unguarded gates whose keepers must have fled in fear. Pedestrians had vanished. The night seemed unnaturally hushed, as if holding its breath until the danger passed. Sano reached the waterfront and found it deserted. Were the harbor police also hiding from the ghosts? A slither of dread crept into Sano’s bones. As a veteran of the shōgun’s unsuccessful hunts for ghosts, he had good reason to doubt any existed, but now his ingrained superstition prevailed. To dispel fear, Sano sought a rational explanation for what he’d seen.