At the sound of footsteps in the corridor, Sano looked up to see Hirata and the castle physician enter the room. They crouched beside him, cloths held over their noses and mouths, studying Lady Harume’s corpse.

“What disease was this, Dr. Kitano?” Sano spoke through his own cloth, which was now wet with saliva.

The doctor shook his head. He had a lined face, and thin gray hair knotted at his nape.”I don’t know. I’ve been a physician for thirty years, but I’ve never seen or heard of anything like this before. The sudden onset, the violent delirium and convulsions, the dilated pupils, the rapid demise… It’s a mystery to me; I know of no cure. The gods help us if this disease should spread.”

Hirata said, “During my first year in the police service, a fever killed three hundred people in Nihonbasbi. Not with those symptoms, or so quickly, but it caused serious trouble. Shops were deserted by owners who had died or run for the hills. Fires started because people burned candles and incense to purify their homes and keep away the fever demon. Bodies lay in the streets because they couldn’t be taken away fast enough. The smoke from all the funerals made a big, black cloud over the whole city.”

Sano covered Harume’s corpse with the shroud, stood, and put away his facecloth, as did his companions. He remembered the epidemic and dreaded an even more disastrous repeat here, in the heart of Japan ’s government. But because of his observations, another, equally disturbing alternative occurred to him.

“Had Lady Harume displayed any signs of illness before now?” he asked Dr. Kitano.

“Yesterday I personally conducted her monthly examination, as I do for all the concubines. Harume was in perfect health.”

Even as Sano’s fear of an epidemic waned, he felt a growing sense of unease.”Are any of the other women sick?”

“I haven’t examined them all yet, but the chief lady official tells me that although they’re upset, they’re physically well.”

“I see.” Though this was Sano’s first visit to the Large Interior, he knew of its crowded conditions.”The women live together, sleep together, bathe together, eat the same food, and drink the same water? And they and the staff are in constant contact with one another?”

“That is correct, sōsakan-sama,” the doctor said.

“Yet no one else shares Lady Harume’s symptoms.” Sano exchanged glances with Hirata, whose face showed dawning-and dismayed- comprehension.”Dr. Kitano, I think we must consider the possibility that Lady Harume was poisoned.”

The doctor’s worried expression turned to one of horror.”Lower your voice, I beg you!” he said, though Sano had spoken softly. Casting a furtive glance toward the corridor, he whispered, “In this day and age, poison is often a possibility in a case of sudden, unexplained death.” Indeed, Sano knew that it was used commonly in peacetime by people who wanted to attack their enemies without open warfare.”But are you aware of the dangers of making such a claim?”

Sano was. News of a poisoning-whether actual or conjectured- would create an atmosphere of suspicion just as destructive as an epidemic. The legendary hostilities in the Large Interior would escalate, and might even turn violent. This had happened in the past. Shortly before Sano came to the castle, two concubines had ended an argument in a brawl, the winner stabbing the loser to death with a hairpin. Eleven years ago, an attendant had strangled a female palace official in the bath. Panic could spread to the rest of the castle, intensifying existing rivalries and provoking fatal duels among samurai officials and troops.

And what if the shogun, ever sensitive to challenges to his authority, should perceive the murder of a concubine as an attack upon himself? Sano envisioned a bloody purge of potential culprits. Seeking a possible conspiracy, the bakufu-Japan’s military government-would investigate every official, from the Council of Elders down to the most humble clerks; every servant; every daimyo-provincial lord-and all their retainers; even the lowliest rōnin. Politically ambitious individuals would try to advance themselves by casting aspersions upon their rivals. Evidence would be manufactured, rumors circulated, characters maligned, until one or many “criminals” were executed…

“We have no proof that Lady Harume was murdered,” Dr. Kitano said.

Noting the man’s pallor, Sano knew he feared that, as chief physician, with a knowledge of drugs, he would be the prime suspect in a crime involving poison. Sano himself had no desire to face the bakufu’s scrutiny, because he had a powerful enemy eager for his ruin. The image of Chamberlain Yanagisawa flashed through Sano’s mind. Sano now had a wife and in-laws, also vulnerable to attack. In Nagasaki he’d learned the dire consequences of indulging curiosity by probing sensitive matters…

Yet, as always at the beginning of an investigation, Sano found himself entering a realm where higher concerns outweighed personal, practical ones. Duty, loyalty, and courage were the cardinal virtues of Bushido-the Way of the Warrior-the foundation of a samurai’s honor. But Sano’s personal concept of honor encompassed a fourth, equally important cornerstone: the pursuit of truth and justice, which gave his life meaning. Despite the risks, he had to know how and why Lady Harume had died.

Also, if she had been murdered, there might be more deaths unless he took action. This time his personal desires coincided with the interests of security and peace in Edo Castle, for good or bad.

“I agree that we can’t rule out disease yet,” Sano said to Dr. Kitano.”An epidemic is still a possibility. Finish your examination of the women, keep them quarantined, and report any cases of illness or death to me immediately. And please have someone take Lady Harume’s body to Edo Morgue.”

“ Edo Morgue?” The doctor gaped.”But sōsakan-sama, high-ranking castle residents don’t go there when they die; we send them to Zōjō Temple for cremation. Surely you know this. And Lady Harume cannot be removed yet. A report documenting the circumstances of her death must be filed. The priests must prepare the body for the funeral, and her comrades keep an overnight vigil. It’s standard procedure.”

During such rituals the corpse would deteriorate, and evidence possibly get lost.”Arrange Lady Harume’s transport to Edo Morgue,” Sano said.”That’s an order.” Unwilling to say why he wanted the concubine taken to a place where dead commoners, outcasts, and victims of mass disasters such as floods or earthquakes went, Sano knew that a show of authority often yielded better results than explanations.

The doctor hurried off. Sano and Hirata surveyed the room.”The source of the poison?” Hirata said, pointing at the floor near Lady Harume’s shrouded corpse. Two delicate porcelain cups lay on the tatami; their spilled contents had darkened the woven straw.”Maybe someone was with her, and slipped the poison into her drink.”

Sano picked up a matching decanter from the table, looked inside, and saw that a bit of liquor remained.”We’ll take this, and the cups, as evidence,” he said.”But there’s more than one way to administer poison. Perhaps she breathed it.’’ Sano gathered lamps and incense burners.”And what do you make of the tattoo?”

“The character ai, " Hirata said.” ‘Love.’ ” He grimaced in distaste.”Yoshiwara courtesans mark themselves this way to prove their love for their clients-even though everyone knows they really do it to get more money from the men. But I would have thought that the shogun’s concubines were too elegant and refined to stoop to such a low-class custom. Do you think the tattoo has anything to do with Lady Harume’s death?”

“Perhaps.” Sano contemplated the razor, blood-tipped knife, and shaved pubic hairs on the floor.”It looks as though she’d just finished the tattoo before she died.”