CHRISTMAS DAWNED BRIGHT and cold over a strangely sleeping Nuremberg. A fresh snow had fallen in those deepest hours between midnight and sunrise, blanketing the city in a sheet of sparkling white.

As the sun rose, households came awake, fires were stoked, and children ran downstairs to tell their parents of the strange dreams that had visited them in the night. The parents, however, had slept dreamlessly, the most restful sleep they’d had since they were very young.

Smoke curlicued from chimney stacks, joining puffy clouds in the sky.

A small gray dove made an arc through the air over the cobblestoned squares of the city. Above the black trees, it flew over the iron gate of the cemetery, where a sad-faced man laid bright tulips at the door of a crypt. Had the dove been given more than paint for eyes, it would have seen that the flowers had been carved from the coats of wooden soldiers. Their only perfume was faint smoke. But the dove flew on. Smooth wingbeats carried it skimming over rooftops, brushing wingtips against the winter-barren trees, its shadow gliding over the pristine snow. It was as if the city had been erased in the night and redrawn with only houses and the barest outlines of the natural world.

Onward the dove glided, past a squat man in a heavy coat, one of a very few people running errands this early on Christmas morning. Over the empty stalls of the Kindlesmarkt, above the silent steps of the great university with its stone clock tower it flew, and on to the square at Englestrasse, where the fine houses and lawns slept peacefully beneath their frosted quilt.

Here it passed the squat man again, entering the back of a house on the square, ushered in through the servants’ door by a man with hair nearly as white as the snow.

The dove completed its arc smoothly, swooping down to the house on Englestrasse to land in the hands of a young man standing on the roof.

Stefan caught the dove with cold fingers and examined the seals on its wings. Wooden wings, but fingers of flesh and bone. He could not decide which was more remarkable. The dove had flown well this time. Even better than the version he’d set aloft on the Danube. The wintry air hadn’t compromised the clockworks inside. And yet, he was worried. Why had Gullet just slipped in through the Stahlbaums’ back door?

Unlike his own home, the Stahlbaums’ roof had a terrace for taking the sun in summer. He could imagine Marie’s family sipping lemonade and looking down on the square below.

Stefan put the dove back in his coat pocket and stood for a moment, looking out onto the sea of white-capped roofs. His father had gone to visit his mother’s grave. This view above the city was his own way of remembering her.

The air was crisp and sharp. He breathed it in, feeling older and tired, but very much alive.

Behind him, the door opened.

“I thought there was something odd about that bird,” Marie said, coming out onto the landing. She was dressed for the day and bundled in her father’s greatcoat. “Merry Christmas, Stefan. May I join you?”

“Please.”

She stepped up to the wrought-iron railing beside him and shoved her hands into her drooping sleeves. The coat was much too big for her, but she wore it like it was her own. Stefan’s own coat fit him perfectly, at last.

“Strange,” she said. “How normal everything looks in daylight.”

The snow had covered much of the night’s damage. Samir and Zacharias had cleared the street of debris. The scorched pavement left by the burning toy soldiers and the war-ravaged lawn in the square center would have been apparent, however, if not for this fortuitous snowfall.

“I’m sure the Brotherhood had something to do with it,” Stefan said. He pulled the dove from his pocket again and began to fiddle with it. “Do you know why Gullet is here?”

Marie shrugged. “Is that the toad of a man who’s come to visit Uncle Christian? I gather he wanted to get a look at me.”

“At you? Why?” Stefan said.

Marie shoved against him with her shoulder. “Again with the flattery. Honestly, Stefan, it takes an army of mice for you to say anything a girl might want to hear.”

Stefan cringed, but found he was smiling. “Sorry. You know what I meant.”

She gave him an arch look. “Well, Herr Gullet is interested in my role in last night’s affair. It seems no one has been able to talk to the cats in quite some time.”

“But you didn’t really—” he began.

She shrugged, smiling like the proverbial cat with tail feathers already in its mouth. “Apparently, I did. And it’s earned me some sort of scholarship.”

Stefan put the dove away one more time. “What are you saying?”

Marie broke into a grin and grabbed his hands. “I’m going to the Pagoda Tree! To study animals and kingdoms and cats and everything. I don’t know how Herr Gullet did it, but he’s impressed my father. And Christian . . . well, he’s working on Mother as we speak. But he’ll convince her, I know it. I’m going to be a part of your world!”

Stefan allowed her to swing him around, a happy circle that stopped suddenly when he dropped her hands. “Marie. This world, it’s not as wonderful as it might sound. Last night we did horrible things.”

Marie grew serious. “Stefan Drosselmeyer, you dolt. Why do you think we did horrible things? Because we didn’t know any better. Ignorance is the refuge of the . . . ignorant. Imagine if we had ambassadors to the other kingdoms. What conflicts we could avoid. All of this might have been resolved by negotiation long ago. Before pride and accidents got in the way. Honestly, I finally meet a boy and he’s dumb as a stump.”

“Hey,” Stefan snapped back. “No tree jokes.”

Marie’s glare was hot enough to melt snow. And then she laughed.

He couldn’t help but laugh, too. They collapsed against each other until they sighed and stopped, Marie’s cheek pressed against his chest.

His arm went around her waist as if it was the most natural thing in the world. “The Pagoda Tree,” he said softly.

“Yes.” Her glossy brown hair smelled of orange blossoms. “If the universe truly is a clock, perhaps knowledge is the key that winds it.”

Stefan buried his nose in her hair, breathing in the scent of spring on Christmas Day. “Thank you,” he said.

Marie’s impish face was mere inches from his own. “For what?”

“For this.”

He leaned in and kissed her, and she kissed him back, and Christmas, and the world, went on for a little while without them.