Which meant one of two things: either Mehmed did not trust him, or Mehmed had deliberately withheld information because he had been looking for a way to get Radu into the city from the very beginning, and he had suspected Radu would be caught and tortured.

Even with the armor of Mehmed’s warning, either option broke Radu’s battered heart.

By nightfall the ditches were filled enough for the towers to cross them. Their progress was as slow and inevitable as the passage of the sun. As near as anyone could tell, men in the bottom pushed, inching them forward. The rain of arrows from the towers had not stopped. No counterattack could be launched, no run on the towers was possible. They crept forward at an agonizing pace, slowly bringing the city’s doom. And still Radu had not found Cyprian. At this point he could not leave—because he did not have his friend, and because it would look as though he was running away.

Someone rode across the space between the walls on a horse pulling a heavily laden cart.

“Giustiniani!”

It was Cyprian. Radu perked up. The city was going to fall, but Cyprian was here! Radu could get him out, and they could get to Nazira and flee. Radu crouched, running along the wall to the ladder, then climbed down.

Cyprian was standing in the cart, arrows falling around him as he pushed a barrel off the end. Radu grabbed a discarded shield and ran forward, climbing on next to Cyprian and covering him while he worked. “We need to go!” Radu shouted.

“Almost finished!” An arrow thunked against the shield over their heads. Cyprian paused, giving Radu that smile that changed his whole face. “Well, that is another life I owe you. One of these days you will have to determine how I can repay you.”

“What is this?” Radu asked as a few other men who had come to help lifted barrels down.

“Gunpowder.”

“The cannons are too small to do enough damage to the towers.”

Cyprian’s grin shifted to something less warm but more appropriate to their surroundings. “Not for the cannons. Get these on the wall!” he shouted.

Radu jumped down, still shielding Cyprian as he directed the men. He kept looking toward the gate, wondering how he could get himself and Cyprian out. Meanwhile, Cyprian continued, oblivious to Radu’s desperation. It was no small task leveraging the heavy barrels up the narrow ladders. They managed awkwardly, losing one man to an arrow. Radu followed Cyprian as they rolled the barrels along until they were positioned directly in front of the tower. Maybe if he helped Cyprian accomplish whatever he was doing, Radu could trick him into leaving.

Giustiniani gestured with concern. “This is nearly all the gunpowder we have left.”

“It is doing us no good in the cannons,” Cyprian said. “This is our best chance.”

“But we do not have enough to take out all the towers. There are several more.”

“The sultan does not know that, does he?”

Understanding dawned on Radu as Cyprian worked long fuses into the tops of the barrels. “You are going to blow up the towers.” Radu laughed, his throat hoarse from exhaustion and smoke. It was exactly what Lada would have done. He should have thought of it himself.

No. He was not actually on this side. Radu tapped his head against the stones beside him, trying to knock some sense into himself. He should do something to prevent it. But he was trapped. He could not do anything for Mehmed, and he could not do anything to risk Cyprian’s life.

Cyprian patted his vest, swearing. “I do not have a flint.”

Radu held out his own. When Cyprian’s fingers met his, there was a spark unrelated to the flint. Radu swallowed the mess of emotions blocking his throat and his breath.

Cyprian grinned at him, then struck the flint and lit the fuse. “If it bursts open when it hits the ground, we are blowing ourselves up.”

Radu shrugged, sitting back. Perhaps that would be a kindness at this point. “At least I will have good company in hell.”

Cyprian laughed. Giustiniani glared at them both. “On three,” Cyprian said. The two other barrels were a few feet away. “One … two … three!”

Radu and Cyprian pushed the barrel up and over the wall while other soldiers did the same with theirs. They braced for an explosion, but none came. They peered over, holding their breath and watching as the barrels tumbled and rolled away from the wall and toward the tower. Giustiniani’s veered too far to the right, lodging in debris. The third barrel lost momentum halfway there. But Cyprian’s kept going, rolling right to the base of the tower.

“Get down!” Cyprian shouted, pulling Radu flat. Radu covered his ears, but the explosion was still deafening. He felt the concussive force of the blast passing right through him. The world hung in stillness for one soundless moment. Then debris pinged against the barrels, against his back, falling everywhere.

The tower was on its side, ripped open. Men ran forward to help the fallen Ottomans, not accounting for the other barrels. Radu and Cyprian ducked again, two more blasts coming in quick succession.

The scent of gunpowder almost covered the stench of burning flesh.

Giustiniani stood, pointing to a group of soldiers standing at the ready behind a sally port. “Burn everything! Kill anyone still moving!”

The port was flung open and men ran out. It was quick work, killing any Ottomans still alive and stunned from the last explosion. They poured pitch onto what was left of the tower’s wooden frame and wheels. When lit, it burned so brightly that Radu could feel the flames warm his face.

Cyprian turned away from the killing, pulling his knees up and resting his head on them. His shoulders were shaking.

“Are you hurt?” Radu’s hand hovered above the other man’s arm. He did not dare touch him. Not on purpose, not in tenderness. He had defied Mehmed’s order to stay safe because he could not abandon Cyprian. And in doing so, he had helped defeat this newest, best chance at the end of the siege. How many ways could a man turn traitor in one lifetime?

Cyprian looked up. Radu could not tell if he was laughing or crying. “I really thought that would blow us up. I thought there was a very good chance I was taking down our own walls and letting him in.”

“But you tried it anyway?”

Cyprian wiped under his eyes, which left his face smeared with soot. “He is attacking us from every possible angle. Below the walls, outside them, above them. From the land, from the sea. He does not need everything to work. Just one thing. And eventually, something will.” Cyprian leaned his head back, looking up at the smoke above them. “But not tonight,” he whispered.