Back on the jet, the two of them had poured over the cryptogram. Vigor was better with ancient languages. But it proved no use. Decoding was made especially difficult because they didn't know which of the four surfaces of the obelisk was the starting point, and in which direction it should be read, clockwise or counterclockwise.
That created eight possibilities.
Vigor had finally rubbed his eyes, admitting defeat. "Without the third key, we'll never figure this out."
Gray refused to believe that. The two had even gotten into a brief argument. They mutually decided to take some time apart, to quit banging their heads together over the riddle. Gray knew much of the shortness of his temper was tied to the knot in his stomach.
Even now he felt like vomiting. Every time he closed his eyes, he pictured his mother's face. He saw the blame in his father's eyes.
So Gray stopped closing his eyes and continued to work.
It was all he could do.
Gray stared again at one of the letter-substitution pages.
Seven more possibilities covered the next pages.
Which was right? Where to even begin?
Ahead, a loud snort drew his attention forward. Kowalski had already fallen asleep. Probably before the wheels even left the tarmac.
Vigor shared the neighboring seat, poring over the silk diary yet again. It was surely a dead end. The monsignor scowled at Kowalski's racket and undid his belt. He slid back to join Gray and collapsed in the next seat. He held the scroll in his hands.
A moment of awkward silence stretched.
Gray closed his notebook. "Back there . . . earlier . . ."
"I know." Vigor reached out and gently patted his hand. "We're all worried. But 1 wanted to run something by you. Get your thoughts."
Gray straightened. "Sure."
"I know you want to solve the obelisk's code. But since we're about to land, maybe now's a good time to figure out where on Hormuz Island the third key might be."
"I thought we already knew where to search," Gray said.
Unable to resist he reopened the notebook and tapped the angelic symbol found on the back of the third gold paitzu.
They had compared it to a map of the island and discovered that the blackened circle marked the location of the ruins of an old Portuguese castle, built about a century before the keys were hidden. In its prime, it had been a prominent stronghold. Built on an isthmus and separated by a moat, it had overlooked the town of Hormuz and the best anchorage ports. To those Vatican mystics looking to hide a key for the ages, the castle would have appeared to be a good place.
They were headed to its ruins now.
Vigor nodded. "Yes, the Portuguese castle. But what I meant was why are we searching there. If we knew that, we might figure out what to look for inside the castle ruins."
"Okay, so where do we begin?"
Vigor pointed out Gray's porthole window. The island could be seen ahead. "Hormuz was a major trading port, trafficking in jewels, spices, and slaves. Important enough that the Portuguese invaded during the sixteenth century and built their castle. But during Marco's time, it was also important enough for Kublai Khan to send a young woman of his household here to be married off."
"Kokejin, the Blue Princess."
"It was purely a commercial arrangement. In fact, the Persian king to whom she was betrothed died while Marco and Kokejin were en route. She ended up marrying the man's son. But again it was a marriage of convenience. She ended up dying only three years later. Some say at her own hand, some say because she was pining for another love."
Gray turned. "You don't mean—"
"Even Marco did not marry until after Kokejin was dead. And when Marco did die, he had two treasures in his room. The gold paitzu that Kublai Khan had given to him. But also a golden headpiece, encrusted with jewels." Vigor stared pointedly at him. "A princess's headpiece."
Gray straightened, imagining Marco's long two-year voyage, traveling and exploring exotic lands. Marco was still relatively young when he left Kublai Khan's palace, in his midthirties. Kokejin was seventeen when she left China, nineteen when she reached Persia. It was not impossible to imagine them falling in love, a love that could never last beyond Hormuz.
Gray rubbed at the headache he'd been fighting. He remembered the brick back at Hagia Sophia, the interior glazed in royal blue, a secret hidden in stone. But could the brick also represent Marco's heart, symbolic of his secret love for Kokejin?
"Then we've forgotten another clue left to us," Vigor continued. He lifted the scroll. "The story was embroidered on silk. Why silk?"
Gray shrugged. "It's a material from the Far East, where Marco had traveled."
"Yes, but could it signify something more?"
Gray remembered Vigor bent over the scripture, even examining it with a loupe. "What did you discover?" he asked.
The monsignor lifted the scroll. "This silk was not new when it was embroidered with the text. The silk was worn thin and uneven. I found oils and old stains."
"So it was a used piece of silk."
"But what was it used for?" Vigor asked. "One of the most common uses for silk—due to its expense and rarity—was as shrouds, burial shrouds of royalty."
Vigor waited, staring at Gray. He slowly understood, picturing a hollow blue brick. Amazement crept into his voice. "You think it might be Kokejin's burial shroud."
"Possibly. But if I'm right, then I know what we must search for within that old castle."
Gray knew, too. "Kokejin's tomb."
4:56 P.M.
Seated in the copilot's seat, Seichan had an expansive view of the island as the seaplane dove toward a sheltered bay. It was not a large island, no more than four miles across. Its center was rocky and hilly, with sparse veins of green. Most of its coastlines were cliffs and isolated jagged bays, home to many smugglers' coves. But to the north, the higher slopes fell more gently toward the sea. Here, the land turned greener with date palms and tilled fields, nestling a small township of thatched huts.
From the air, evidence of an older, more extensive city could be spotted: massive foundations, the stones quarried from the island's rock-salt hills; a few crumbled homes, looking more like rubble piles; and a single tall minaret, once used as a lighthouse by the Portuguese.
But none of this was their destination.
The seaplane tipped on a wing and banked over the isthmus that extended north from the old city. Upon the spit of land rested the remains of the old castle. It had once been separated from the ancient city by a wide moat, but it was now silted up, marked only by a sunken line drawn from east to west.