The tunnel entrance was about two hundred meters up the side of the mountain, at the farthest place where a vehicle could climb up the track cut through the jungle and up the slope. Abayon and Moreno were puzzled. They could think of no tactical reason to build such a complex in Hono Mountain. Their puzzlement turned to rage during their second week of surveillance when the Japanese soldiers lined up all the surviving laborers and machine-gunned them, the bodies tumbling into ditches the doomed had been forced to dig before their execution.

As they watched helplessly from the jungle, the people they knew were being killed; Abayon had to hold Moreno back. A group including Moreno's brother had been lined up in front of the smoking barrels of the machine guns, and there was nothing they could do for them, except get themselves killed. He told his best friend as much, while restraining him, but it did little to comfort either of them.

"Vengeance will be ours," Abayon whispered in Moreno's ear as the machine guns spit death, sending the bodies tumbling on top of those who had been killed before them.

"Vengeance," Abayon repeated again and again to Moreno, trying to contain his friend's white hot rage.

"Whatever they have built in the mountain, it must be important. They are killing all who know the way in and what was built. But we know. And we know what they have done here. We will have vengeance."

Moreno was shaking his head, tears streaming down his face. They were on a hill across the valley from Hono, well hidden, but with an excellent view of not only the mountain, but the valley where the executions were taking place.

"What good is vengeance?" Moreno asked.

"It will not bring back the dead."

"It is all we have," Abayon said simply.

"It is what we must feed on. Until every last Japanese soldier is dead."

The distinctive chatter of the Japanese machine guns echoed once more as the last group of laborers were executed. Abayon pointed.

"See that officer?"

Moreno blinked away his tears and nodded. The man had an ornate samurai sword strapped to his side, and the rank insignia on his collar indicated he was a colonel in the Imperial Army.

"I have been watching," Abayon said.

"He is in command. Every soldier and other officer he comes in contact with defers to him. He will be dead within the month. I promise you that. All of them will be dead."

"How?" Moreno asked. They had counted at least three hundred Japanese soldiers on the mountain. Even though most of them appeared to be engineers and not infantrymen, there were still too many for their poorly armed and equipped group to take on.

"I will think of a way," Abayon promised.

Surprisingly, it was the officer he had pointed out who gave him the means.

The next day, as the corpses of the Filipino men and women who had worked in the mountain rotted in their shallow graves, the colonel led a large contingent of his men to the beach to greet a Japanese ship that appeared in the water to the south. They had cut a rough road through the jungle from the mountain to the beach, and now drove a half-dozen small trucks to the edge of the ocean, where they lined up on the sand.

Crate after crate was off-loaded from the ship, brought ashore, and loaded onto the trucks. Abayon and Moreno watched as the trucks made over two dozen trips, hauling crates to the mountain, where the Japanese soldiers man-handled them into the gaping black opening.

"What do you think they are hiding?" Moreno asked as the last load disappeared into the mountain. The ship had already departed, gone over the horizon even as the trucks made their last trip back from the beach. In its place, a small patrol boat was at anchor offshore.

Before Abayon could reply, they heard the chatter of machine-gun fire echo out of the black hole across from them.

"What is going on?" Moreno asked.

"Were there more of our people in there?"

The Japanese colonel appeared in the mouth of the cave with three men. Two of them were firing machine guns back the way they had come. Abayon frowned, trying to make sense of it. The colonel gestured to the third man who was unreeling wire. The man attached the wire to a small box, and it was suddenly clear to Abayon.

"They're sealing the entrance," he said.

The man pushed down the plunger, then dust blew out of the tunnel entrance, the rumble of the explosion drifting across the valley to Abayon and Moreno. A second explosion followed, and the mouth of the tunnel crumbled, leaving behind a tumble of rocks blocking the entrance.

"But where are the rest of the Japanese?" Moreno asked.

Abayon simply pointed. The colonel had his pistol out. He lifted it and fired three times, killing the men who had been with him.

"My God," Moreno muttered.

"What is going? Has he lost his mind?"

"A secret," Abayon whispered, realizing the import of what they had just witnessed.

"He's the only one who knows this location. The jungle will grow over those rocks."

Abayon nodded grimly.

"But we know."

He stood.

"Come."

His eyes were no longer on where the tunnel had been, but on the Japanese officer who was walking down the thin dirt road, unreeling more wire, stopping every so often to attach the leads to charges on trees. The demolitions must have taken days to prepare, Abayon realized as he and Moreno headed into the valley. And the engineers who had prepared them were now trapped inside the mountain, either already dead or dying.

They heard three explosions as they headed toward the road. The colonel was blowing trees on the side of the road. Like the tunnel entrance, it would not take long for the jungle to reclaim the road, hiding what had been there.

They reached the valley floor as a fourth explosion rumbled through the forest, followed by the sound of trees falling. It was not far from their location, less than half a kilometer away, as near as Abayon could tell. He tried to imagine the rationale for building something inside the mountain and then immediately destroying all trace of it and blocking the way in. What had been in those crates? And why was the colonel hiding them even from his own people?

They climbed up out of the stream bed, and the double track trail was in front of them. Abayon signaled to Moreno, and the two took up hidden positions alongside the rutted track. After several minutes the Japanese colonel appeared, hooking up the detonator to fused charges he'd placed on a half-dozen trees spaced out along the way. He did the last one less than one hundred meters from their location and unreeled about half the distance in wire before kneeling and pushing the plunger.

The explosion thundered through the jungle, trees from both sides collapsing across the path, making it impassable for vehicles. The dust-covered colonel retrieved as much of the wire as he could, reeling it up, then turned to continue his destructive journey toward the beach and the waiting patrol boat. Abayon had no doubt what the fate of that crew would be once the colonel returned to civilization.

But that was not going to happen.

As the colonel drew even with their position, Abayon gave Moreno the signal. The two men leapt out of the brush and overwhelmed him as he hooked up the wire to a charge on a tree opposite their location. They had him pinned to the ground within a second, Abayon tying the man's hands securely behind his back. The colonel struggled and fought, but the two guerrillas were too much for him.

Abayon rolled the Japanese over on his back as he unbuckled the samurai sword from around the officer's waist. The colonel kicked out, catching Moreno in the stomach, doubling him over. Abayon drew the sword and placed the point against the man's chest.

"Do not move," he ordered.