The rats came with the warmth, creeping out of the merchant-boats while men unloaded silver and cloth and forged iron for the sticky, sweltering markets of Moscow. They thrived in the smother, drawn to the reek of Moscow’s middens.

The first folk to fall sick lived in the posad: the airless, crowded huts by the river. They began to cough, to sweat, and then to shiver. Then the smooth swellings showed, at throat and groin, and then black spots.

Plague. The word rippled through the city. Moscow had seen plague before. Dmitrii’s uncle Semyon had died of it, with his wife and his sons in one terrible summer.

“Close up the houses of the sick,” said Dmitrii to the captain of his guard. “They are not to go out—no, not even to go to church. If a priest can be found to bless them, let the priest go in, but that is all. Tell the guards at the city-gate; anyone who seems ill is not allowed within the walls.” Folk still whispered in hushed tones of the death of Dmitrii’s uncle: dying swollen like a tick, black-spotted, his own attendants afraid to come near him.

The man nodded, but he was frowning. “What?” Dmitrii demanded. The night of the Tatar attack had decimated Dmitrii’s city guard. In the aftermath of the riot and Vasya’s burning, he’d built it up again, larger than before, but they were still inexperienced.

“This sickness is the curse of God, Gosudar,” said the captain. “Surely it is only right that men be allowed to go and pray? All the people’s prayers together may yet reach the ears of the Almighty.”

“It is a curse that flies from man to man,” said Dmitrii. “What are the walls of Moscow for if not to keep out evil?”

One of his boyars there in his anteroom said, “Forgive me, Gosudar, but—”

Dmitrii turned, scowling. “Can I not give orders without debate from half the city?” Ordinarily he humored his boyars. They were mostly older than he, and had ensured that he had a throne to inherit when he came of age. But the shocking heat sapped his strength and brought on a sick, weary anger. He’d had no word from either of his cousins. The Prince of Serpukhov had taken all the silver Muscovy could muster, and had gone south to plead their case before the temnik Mamai. Sasha was supposed to be bringing back Father Sergei. But Sasha had not returned, and reports came out of the south that Mamai was still gathering up his ulus, as though he’d never heard Vladimir’s message at all.

“The people are afraid,” said the boyar carefully. “Thrice have the dead come walking since the season turned. Now this? If you shut the gates of Moscow and deny church to the sick, I do not know what they will do. Already there is much talk that the city is cursed.”

Dmitrii understood war, and the managing of men, but curses were outside his experience. “I will take thought for the comfort of the city,” he said. “But we are not cursed.” In his own heart, though, Dmitrii wasn’t sure. He wanted Father Sergei’s advice, but the old monk was not there. So instead, grudgingly, the Grand Prince turned to his steward. “Send for Father Konstantin.”