“Yes, Lord Matsudaira,” he said. “You can count on me.”

A month later, Hirata sat in his office with Detectives Inoue and Arai, sorting through the information they’d collected on the potential traitors. He shook his head as he skimmed a document. “We’ve bribed servants, retainers, and family members to spy on all those men, but not one has reported anything that indicates a plot against Lord Matsudaira.”

“We’ve posted listeners all over the castle and town, but they’ve heard nothing to implicate the suspects,” Arai said.

“Maybe they’re innocent,” Inoue said.

“Maybe we’ve wasted a month chasing phantoms of Lord Matsudaira’s imagination.” Frustration filled Hirata. Every day he spent away from his training, he regretted abandoning it. Each morning he practiced the hated meditation and breathing exercises, in hope that he would soon return to Ozuno. “If we don’t find some evidence that those men are traitors, Lord Matsudaira will be displeased rather than relieved.”

He and the detectives sat in silence, picturing themselves demoted, exiled, or put to death because they’d failed to produce the desired results. Arai said, “What should we do next?”

“We mount surveillance on the suspects,” Hirata said. “We pray that we catch them doing something wrong.” The surveillance would take a massive effort. His studies could not resume for months-if they ever did.

“All right. We’ve got twelve men to watch,” Inoue said. “Where do we start?”

“We might as well draw straws,” Hirata said.

A guard appeared at the door and said, “Excuse me, but I thought you would want to see this.” He gave Hirata a rolled-up, flattened paper. “I found it stuck under the back gate while I was making my rounds.”

Hirata unfolded the paper and read the words written there. Surprise interrupted his heartbeat. “Listen.”

If you want to catch a traitor, look no further than Lord Mori. He is leading a conspiracy to overthrow Lord Matsudaira. He is expecting to receive a secret shipment of guns and ammunition at his estate.

“Maybe this is the break we need,” Arai said, voicing Hirata’s hope. Inoue looked skeptical. “Who wrote the letter?”

“There’s no signature, and I don’t recognize the calligraphy.” Hirata asked the guard, “Did you see who left the letter?”

“No. It could have been anybody passing by.”

“Anonymous tips are not to be trusted,” Inoue said.

“But not to be ignored, either.” Hirata knew from past experience that they sometimes told the truth, and he needed every clue that came his way. “If we should catch Lord Mori stockpiling weapons, that would be evidence of treason.”

“And what have we got to lose by choosing him as our first surveillance target?” Inoue said.

Arai nodded. “When do we begin?”

“The letter doesn’t say exactly when he’s due to receive the shipment,” Hirata said. “We should begin our watch tonight.”

The next eleven nights found Hirata, Inoue, and Arai perched on the roof of the mansion across the street from Lord Mori’s estate. Other detectives occupied roofs within estates nearby, whose owners Hirata had ordered to cooperate with his investigation. Gables and trees concealed them. The only person in a position to spot them was the lookout in the local fire-watch tower. Hirata figured that the man wouldn’t dare interfere.

The first ten nights passed without event. No deliveries of any kind arrived for Lord Mori. The rainy season began. Huddled on the roof tiles, deluged by storms, Hirata wondered if the anonymous tip was a hoax and he was suffering for naught. On the eleventh night, Hirata peered at the gate while Arai and Inoue dozed under an oiled cloth they’d rigged up on the roof gable to protect themselves from the endless rain. Halfway between midnight and dawn, he’d begun nodding off himself, when a noise in the street jarred him alert. He wakened Arai and Inoue. They saw two porters lugging a big crate, staggering under its heaviness. Three more pairs, similarly burdened, followed. The porters halted outside Lord Mori’s gate. The guards admitted them. Hirata crawled up to the peak of the roof. Standing on his toes, clinging to the gable for support, he could just see into Lord Mori’s courtyard, where dim lights from a guardhouse shone through the dripping rain. Figures in the building were silhouetted in the windows. Their movements suggested prying open a box with a crowbar and raising the lid. One man held up a long, thin object. He positioned one end against his shoulder and sighted along it.

It was a gun.

Hirata’s heart clamored with exhilaration as he slid down the roof. “Those were the weapons that just arrived,” he told Arai and Inoue. “Let’s gather our troops and raid the estate.”

“Did you find the weapons or any other evidence that Lord Mori was a traitor?” Sano asked Hirata.

They were seated in Sano’s office. The room had a musty smell of damp wood and mildewed tatami. Rain streamed down outside. The morning was as dark as if the sun had drowned.

“Not yet,” Hirata said. “But it’s a big estate. My men are still searching.”

“Well, I hope they find those guns,” Sano said. If Lord Mori could be proved guilty of plotting against Lord Matsudaira, then no one except his own people would care about his murder. Reiko wouldn’t be in as much trouble. “Have you questioned Lord Mori’s guards?”

“My detectives did. The guards deny that they took in the weapons. But of course they would. They wouldn’t want to implicate themselves in treason.”

Chin in hand, Sano contemplated the story Hirata had just told. “Could you have been mistaken about what you saw?”

“I suppose so.” Doubt tinged Hirata’s voice. “But I was certain at the time.”

“Your story doesn’t explain why you happened to raid the estate just in time to discover Lord Mori murdered and my wife at the scene.”

“It must be a coincidence.”

“That’s too big a coincidence as far as I’m concerned.” Sano smelled a setup. “Did you try to find out who sent the letter that put you onto Lord Mori?”

“No,” Hirata said, chagrined. “I know I should have. It just seemed more important to find out whether it had any merit. I’m sorry I didn’t do a more thorough investigation.”

Sano was, too. If Hirata had, they might have had information that could help Reiko. And Sano had even more reason to be concerned. A slapdash job was out of character for Hirata. He’d changed in ways that Sano found disturbing, that boded ill for their relationship as well as the murder case.

“I remember Ozuno from that investigation three years ago,” Sano said. “But I had no idea that he’d made you his disciple.”

“It’s supposed to be a secret.” Hirata was obviously upset that he’d revealed it. “I shouldn’t have told even you.”

But Hirata’s first loyalty was to Sano, and not just because Sano was his master. Hirata owed his high rank and all its associated honors to Sano.

“You won’t tell anybody, will you?” Hirata said anxiously.

“Not unless it’s necessary, and right now I don’t see why it would be,” Sano said. Obligation worked both ways with them.

Hirata let out a breath of relief. “Then you don’t object to my training with Ozuno?”

Sano hesitated. Training with a master such as Ozuno was a once-in-a-lifetime opportunity. Furthermore, Sano couldn’t begrudge Hirata the chance to overcome his physical weakness: Hirata had been wounded in the process of saving Sano’s life.

“No. But I must caution you,” Sano said. “It’s not just my approval that you should worry about. Next time you go off to a training session, Lord Matsudaira and the shogun might not forgive you.”

“I know.” Hirata sounded torn between samurai duty and personal desire.

“And it was dangerous to allow your training to interfere with your duty,” Sano went on. “You put yourself under too much pressure to placate Lord Matsudaira, all the while you’re in such a hurry to return to your lessons that you’re skipping important steps.”