The Tōkaidō, the great Eastern Sea Road, extended west from Edo toward the imperial capital at Miyako. Fifty-three post stations-villages where travelers lodged and the Tokugawa regime maintained security checkpoints-dotted the highway. West of the tenth post station of Odawara, the highway cut across the Izu Peninsula. The terrain ascended into the mountainous district over which reigned the massive volcano Mount Fuji. Here the Tōkaidō carved a crooked path upward through forests of oak, maple, cedar, birch, cypress, and pine.

Along this stretch of road moved a procession comprised of some hundred people. Two samurai scouts rode on horseback ahead of foot soldiers and mounted troops. Banner bearers held a flag emblazoned with the Tokugawa triple-hollyhock-leaf crest, leading ten palanquins followed by servants. Porters carrying baggage preceded a rear guard of more mounted troops and marching soldiers. Syncopated footsteps and the clatter of the horses’ hooves echoed to distant peaks obscured by dense gray clouds.

Inside the first palanquin, Reiko and Lady Keisho-in rode, seated opposite each other. They watched through the windows as occasional squadrons of samurai overtook them or commoners passed from the other direction. Moisture condensed in the cool afternoon; streams and waterfalls rippled; birdsong animated the forest.

“Four days we’ve been traveling, and we’re still not even near Fuji-san,” Keisho-in said in a grumpy tone.

Reiko forbore to point out that their slow pace was Keisho-in’s own fault. Keisho-in had spent hours buying souvenirs and sampling local foods at every post station. She’d often ordered the procession to halt while she greeted the public. Furthermore, she disliked riding fast. The women had now gone a distance that should have taken them half the time and a fast horseman could cover in a day. And the trip had already taxed Reiko’s endurance.

The group had gotten little sleep due to late, noisy, drunken parties hosted by Keisho-in every night at the inns where they’d stayed. Reiko, forced to share chambers with Lady Yanagisawa, had hardly dared close her eyes at all. Now fatigue weighed upon her; yet she couldn’t even doze in her palanquin, because someone always needed her company. Keisho-in didn’t want to ride with Midori, who took up too much space, or Lady Yanagisawa, whose reticence bored her. Midori said Lady Yanagisawa frightened her, and Lady Yanagisawa could bear no one except Reiko. Hence, Reiko divided her time between her three companions.

“This climate makes my bones hurt,” Keisho-in complained. She extended her legs to Reiko. “Massage my feet.”

Reiko rubbed the gnarled toes, hoping not to arouse desire in her companion. So far Lady Keisho-in had satisfied herself with the soldiers, or the ladies-in-waiting and maids who rode in the last six palanquins. But Reiko feared that Keisho-in’s roving eye would turn on her. Estimating at least another two days on the road before they arrived at their destination, Reiko sighed. Mount Fuji, hidden by the clouds, seemed as far as the end of the world, and her return home seemed eons away. She prayed that something would happen to cut short this trip.

The road angled through a gorge bordered by high, steep cliffs. Crooked pines clung to the eroded earth. Pebbles skittered down the cliffs to the road. As the procession moved onward, the cliff on its right gave way to level forest. The road curved out of sight between tall, aromatic cedars on one side and sheer rock on the other. Reiko’s senses tingled at a change in the atmosphere. Suddenly alert, she froze.

“Why have you stopped massaging?” Keisho-in said irritably.

“There’s something wrong.” Reiko put her head out the window and listened. “It’s too quiet. I don’t hear any birds, and no one has passed us in a long while.”

A rush of fear assailed Reiko; her heartbeat accelerated. In front of the palanquin rode Sano’s two detectives, and Reiko saw them turn their heads and sweep their gazes across the landscape, as if they, too, perceived danger. Then she heard hissing noises. Torrents of slender shafts whizzed down from the cliff top. A soldier screamed and collapsed with an arrow protruding from his neck. The procession dissolved into chaos as men dodged the arrows and horses bolted. Reiko ducked back inside the window.

“What is happening?” Lady Keisho-in demanded.

“Someone’s shooting at us. Get down!” Reiko pushed Lady Keisho-in onto the cushioned floor of the palanquin and slammed the windows shut.

More arrows thudded against the palanquin’s roof. Shouts burst from the troops and servants, anxious twittering from the women in the other palanquins.

Outside, the guard captain shouted, “We’re under attack! Run forward! Stay together!”

The palanquin lurched, gathering speed, jolting as the bearers trotted. Hoofbeats pounded amid screams. The air whirred with the quickening storm of arrows. Their steel points clattered on the road, rang against armor, struck human flesh with meaty thumps. Men bellowed in agony, then the palanquin crashed to the ground with an impact that broke the windows off their hinges and jarred Reiko against Lady Keisho-in.

“Our bearers have been killed.” Horror flooded Reiko as she looked outside and saw the men sprawled beneath their shoulder poles. “We can’t move.” Up the road, arrows felled running soldiers in their tracks. Horses galloped past the dead, crumpled bodies of their riders, after the mounted troops of the advance guard. Behind Reiko, the procession had stalled. “And we’re blocking everyone else’s way.”

The other bearers set down their palanquins; porters dropped baggage. The advance guard reversed its flight, hastening to defend the procession. “Everyone hide in the forest!” shouted the captain.

Servants, porters, and bearers fled down the banked roadside, into the shadowy haven between the trees.

“They’re abandoning us!” Lady Keisho-in cried, indignant.

Troops thundered up alongside the row of palanquins, shouting for the ladies to get out. Reiko grabbed Keisho-in by the hand. “Come on.”

As they exited the palanquin, Reiko saw Midori, Lady Yanagisawa, and the female attendants emerge from their vehicles. Then screams blared from the forest. People who’d taken cover there came running out, their faces masks of terror. The woods disgorged upon them a horde of men armed with swords and clad in armor tunics and leg guards, chain-mail sleeves, and metal helmets. Black hoods, with holes for the eyes, covered their faces. The men chased the attendants, slashing their blades at porters who dropped dead on the highway with bloody wounds across their naked backs. The savagery struck Reiko mute; shock momentarily paralyzed her.

“Bandits!” cried Lady Keisho-in.

The other women babbled in fright. The captain shouted, “Ladies, get back in the palanquins!”

Reiko thrust the shogun’s mother inside, leapt in after her, and closed the door. Outside, the attackers slaughtered servants, pursued those who fled.

“Merciful gods,” Reiko said, astounded as well as aghast. “Who dares attack an official Tokugawa procession?”

The captain shouted orders to his army. While a few troops guarded the palanquins, foot soldiers and mounted samurai launched a defense. Blades lashed hooded men; horses trampled them. But more attackers erupted from the forest, outnumbering the sixty troops that had seemed adequate protection during peacetime. Now every soldier battled multiple opponents. Mounted warriors circled, surrounded by their foes, their horses rearing; their blades whistled arcs in the air. Hooded men dropped, but their comrades slashed the riders dead in their saddles, or dragged them down and slew them. Foot soldiers whirled in desperate dances, weapons flashing. Scarlet gashes from enemy blades appeared on their bodies, and their garments flew in tatters, until they expired from mortal injuries.