But not completely.

Not until he had some answers about the murder.

Reaching his locker, he tugged the door open and caught his BlackBerry as it rattled across the bottom of the metal locker. It had to be Director Crowe. As his fingers closed on it, the vibration ceased. He’d missed the call. He checked the log and frowned. It was not Painter Crowe.

The screen read: R. Trypol.

He had almost forgotten.

Captain Ron Trypol of Naval Intelligence.

The captain had been overseeing the salvage operations at the Indonesian island of Pusat. He had a report due today on his assessment of raising the sunken cruise ship, the Mistress of the Seas. He had two navy submersibles on site, searching the wreckage and surrounding area.

But Gray had a more personal interest in the search.

The island of Pusat was where his friend and partner, Monk Kokkalis, had last been seen, spotted as he was dragged under the sea by a weighted net, tangled and caught. Captain Trypol had agreed to look for Monk’s body. The captain was a good friend and former colleague of Monk’s widow, Kat Bryant. This morning, Gray had gone over to the National Maritime Intelligence Center in Suitland, Maryland, hoping to hear any word. He had been rebuffed, told to wait until after the full debriefing. It was why he had been storming back here, prepared to demand that the director pressure the navy.

Flushed with a twinge of guilt for having set aside his cause, Gray hit the callback button and lifted the phone to his ear. As he waited for the connection to NMIC, he sank to a bench and stared at the locker on the opposite side. Written in black marker across a strip of duct tape was the name of the locker’s former owner.

KOKKALIS.

Though Monk was surely dead, no one wanted to remove the tape. It was a silent hope. If only sustained by Gray.

He owed his friend.

Monk had climbed through the ranks of Sigma alongside Gray. His friend had been recruited from the Green Berets at the same time as Gray had been pulled from Leavenworth prison, where he’d been incarcerated after striking a superior officer during his stint with the Army Rangers. They had become quick friends, if not a bit of an odd couple at Sigma. Monk stood only a few inches over five feet, a shaven-headed pit bull compared to Gray’s taller, leaner physique. But the true difference lay deeper than mere appearance. Monk’s easygoing manner had slowly tempered the uncompromising steel of Gray’s heart. If not for Monk’s friendship, Gray would have certainly washed out of Sigma, as he had the Army Rangers.

As he waited, Gray pictured his former partner. They’d been through countless scrapes together over the years. Monk bore the puckered bullet wounds and scars to prove it. He had even lost his left hand during one mission, replaced with a prosthetic one. As he sat, Gray could still hear the barking bellow of Monk’s laugh…or the quiet intensity of his voice, revealing the man’s genius-level I.Q., disciplined in forensic medicine and science.

How could someone so large and vital be gone? Without a trace?

The phone finally clicked in his ear. “Captain Ron Trypol,” a stern voice answered.

“Captain, it’s Gray Pierce.”

“Ah, Commander. Good. I had hoped to reach you this afternoon. I don’t have much time before my next meeting.”

Gray already heard the dire overtones. “Captain?”

“I’ll get to the point. I’ve been ordered to call off the search.”

“What?”

“We were able to recover twenty-two bodies. Dental records show none of them to be your man.”

“Only twenty-two?” Even by conservative estimates, that was only a small fraction of the dead.

“I know, Commander. But recovery efforts were already hampered by the extreme depths and pressures. The entire bottom of the lagoon is riddled with caverns and lava tubes, many extending miles in tangled mazes.”

“Still, with—”

“Commander.” The man’s tone was firm. “We lost a diver two days ago. A good man with a family and two children.”

Gray closed his eyes, knowing the ache of that loss.

“To search the caves only risks more men. And for what?”

Gray remained silent.

“Commander Pierce, I assume you haven’t heard any more word. No further cryptic messages?”

Gray sighed.

To gain the captain’s cooperation, he had related the one message he had received…or possibly received. It had occurred weeks after Monk had vanished. Following the events that occurred at the island, the only piece of his friend to be salvaged had been his prosthetic hand, a state-of-the-art piece of biotechnology built by DARPA engineers, which included a built-in wireless radio interface. While transporting the disembodied hand to Monk’s funeral, the prosthetic fingers had begun to tap out a weak S.O.S. It had lasted only a few seconds—and only Gray had heard it. Then it had gone silent. Technicians had examined the hand and concluded it was most likely a mere glitch. The hand’s digital log showed no incoming signal. It was just a malfunction. Nothing more. An electrical ghost-in-the-machine.

Still, Gray had refused to give up—even as week after week passed.

“Commander?” Trypol said.

“No,” Gray admitted sullenly. “There’s been no further word.”

Trypol paused, then spoke more slowly. “Then perhaps it’s time to lay this to rest, Commander. For everyone’s sake.” His voice softened at the edges. “And what about Kat? Your man’s wife. What does she have to say about all this?”

It was a sore point. Gray wished he’d never mentioned it to her. But how could he not? Monk was her husband; they had a little girl together, Penelope. Still, maybe it had been the wrong thing to do. Kat had listened to Gray’s story with a stoic expression. She stood in her black funeral dress, ramrod straight, her eyes sunken with grief. She knew it was a thin lifeline, only a frail hope. She had glanced to Penelope in the car seat of the black limousine, then back to Gray. She didn’t say a word, only shook her head once. She could not grasp that lifeline. She could not survive losing Monk a second time. It would destroy her when she was already this fragile. And she had Penelope to consider, her own piece of Monk. True flesh and blood. Not some phantom hope.

He had understood. So he had continued his investigation on his own. He had not spoken to Kat since that day. It was a silent, mutual pact between them. She did not want to hear from him until the matter was resolved one way or the other. Gray’s mother, though, spent several afternoons with Kat and the baby. His mother knew nothing about the S.O.S., but she had sensed that something was wrong with Kat.

Haunted, that was how his mother had described Kat.

And Gray knew what haunted her.

Despite what Kat had decided that day, she had grasped that lifeline. What the mind attempted to set aside, the heart could not. And it was torturing her.

For her sake, for Monk’s family, Gray needed to face a harsh reality.

“Thank you for your efforts, Captain,” Gray finally mumbled.

“You did right by him, Commander. Know that. But eventually we have to move on.”

Gray cleared his throat. “My condolences for the loss of your man, sir.”

“And the same to you.”

Gray ended the connection. He stood for a long breath. Finally, he stepped over to the opposite locker, placed a palm on its cold metal surface, as cold as a grave.

I’m sorry.

He reached up, peeled a corner of the duct tape, and ripped it away.

Gray was done chasing ghosts.

Good-bye, Monk.

4:02 P.M.

Painter spun the ancient coin atop his desk. He watched the silver flash as he concentrated on the mystery it represented. It had been returned from the lab half an hour ago. He had read the detailed report that had accompanied it. The coin had been laser-mapped for fingerprints, both its metallic content and surface soot had been analyzed with a mass spectrometer, and a multitude of photographs had been taken, including some taken with a stereo-microscope. The coin’s spinning slowed, and it toppled to the mahogany desktop. Carefully cleaned, the ancient image on the surface shone brightly.

A Greek temple supported by six Doric pillars.

In the center of the temple rested a large letter.

E

The Greek letter epsilon.

On the opposite side was the bust of a woman with the words DIVA FAUSTINA written below it. From the report, at least the origin of the coin was no longer a mystery.

But what did—?

His intercom chimed. “Director Crowe, Commander Pierce has arrived.”

“Very good. Send him in, Brant.”

Painter pulled the research report closer to him as the door swung open. Gray stepped through, his black hair wet and combed. He had changed out of his bloody clothes and wore a green T-shirt with ARMY emblazoned on the front, along with black jeans and boots. As he entered, Painter noted a shadow over the man’s features, but also a certain weary resolve in his gray-blue eyes. Painter could guess the reason. He had already heard from the Office of Naval Intelligence through his own channels.

Painter waved Gray to a seat.

As he sat, the man’s attention noted the coin on his desk. A flicker of curiosity flared.

Good.

Painter shifted the coin toward Gray. “Commander, I know you asked for an indeterminate leave of absence, but I’d like you to take the lead on this case.”

Gray made no move to take the coin. “May I ask a question first, sir?”

Painter nodded.

“The dead man. The professor.”

“Archibald Polk.”

“You mentioned that he must have been on his way here. To see you.”

Painter nodded. He suspected where the line of questioning was leading.

“So Professor Polk was familiar with Sigma? Despite the top secret clearance for such knowledge, he knew about our organization?”

“Yes. In a manner of speaking.”

Gray’s brow crinkled. “What manner is that?”

“Archibald Polk invented Sigma.”

Painter took a small measure of satisfaction in the man’s surprise. Gray needed a little shaking up. The man sat up straighter in his chair.