There was no answer.

Suddenly, Nora found herself running. She arrowed down the aisle, sprinting as fast as she could. Swift footfalls sounded in the adjoining aisle.

Ahead was a gap, where her aisle joined the next. She had to get past, outrun the person in the adjoining aisle.

She dashed through the gap, glimpsing for a split second a huge black figure, metal flashing in its gloved hand. She sprinted down the next aisle, through another gap, and on down the aisle again. At the next gap, she veered sharply right, heading down a new corridor. Selecting another aisle at random, she turned into it and ran on through the dimness ahead.

Halfway to the next intersection, she stopped again, heart pounding. There was silence, and for a moment relief surged through her: she had managed to lose her pursuer.

And then she caught the sound of faint breathing from the adjoining aisle.

Relief disappeared as quickly as it had come. She had not outrun him. No matter what she did, no matter where she ran, he had continued to pace her, one aisle over.

“Who are you?” she asked.

There was a faint rustle, then an almost silent laugh.

Nora looked to the left and right, fighting back panic, desperately trying to determine the best way out. These shelves were covered with stacks of folded skins, parchment-dry, smelling fearfully of decay. Nothing looked familiar.

Twenty feet farther down the aisle, she spied a gap in the shelving, on the side away from the unknown presence. She sprinted ahead and turned into the gap, then doubled back into yet another adjoining aisle. She stopped, crouched, waited.

Footfalls sounded several aisles over, coming closer, then receding again. He had lost her.

Nora turned and began moving, as stealthily as possible, through the aisles, trying to put as much distance as possible between herself and the pursuer. But no matter which way she turned, or how fast she ran, whenever she stopped she could hear the footfalls, rapid and purposeful, seeming to keep pace.

She had to figure out where she was. If she kept running around aimlessly, eventually he—it—would catch her.

She looked around. This aisle ended in a wall. She was at the edge of the Archives. Now, at least, she could follow the wall, make her way to the front.

Crouching, she moved along as quickly as she could, listening intently for the sound of footsteps, her eye scanning the dimness ahead. Suddenly, something yawned out from the gloom: it was a triceratops skull, mounted on the wall, its outlines shadowy and vague in the poor light.

Relief flooded through her. Puck must be around here somewhere; the intruder wouldn’t dare approach them simultaneously.

She opened her mouth to call out softly. But then she paused, looking more closely at the dim outline of the dinosaur. Something was odd—the silhouette was all wrong. She began to move cautiously toward it. And then, abruptly, she stopped once again.

There, impaled on the horns of the triceratops, hung a body, naked from the waist up, arms and legs hanging loose. Three bloody horns stuck right through the man’s back. It looked as if the triceratops had gored the person, hoisting him into the air.

Nora took a step back. Her mind took in the details, as if from a long distance away: the balding head with a fringe of gray hair; the flabby skin; the withered arms. Where the horns had speared through the lower back, the flesh was one long, open wound. Blood had collected around the base of the horns, running in dark rivulets around the torso and dripping onto the marble.

I’m on the triceratops in the back.

In the back.

She heard a scream, realized that it had come from her own throat.

Blindly, she wheeled away and ran, veering once, and again, and then again, racing down the aisles as quickly as she could move her legs. And then, abruptly, she found herself in a cul-de-sac. She spun to retrace her steps—and there, blocking the end of the row, stood an antique, black-hatted figure.

Something gleamed in his gloved hands.

There was nowhere to go but up. Without an instant’s thought, she turned, grabbed the edge of a shelf, and began climbing.

The figure came flying down the aisle, black cloak billowing behind.

Nora was an experienced rock climber. Her years as an archaeologist in Utah, climbing to caves and Anasazi cliff dwellings, were not forgotten. In a minute she had reached the top shelf, which swayed and groaned under the unexpected weight. She turned frantically, grabbed the first thing that came to hand—a stuffed falcon—and looked down once again.

The black-hatted man was already below, climbing, face obscured in deep shadow. Nora aimed, then threw.

The falcon bounced harmlessly off one shoulder.

She looked around desperately for something else. A box of papers; another stuffed animal; more boxes. She threw one, then another. But they were too light, useless.

Still the man climbed.

With a sob of terror, she swung over the top shelf and started descending the other side. Abruptly, a gloved hand darted between the shelving, caught hold of her shirt. Nora screamed, ripping herself free. A dim flash of steel and a tiny blade swept past her, missing her eye by inches. She swung away as the blade made another glittering arc toward her. Pain abruptly blossomed in her right shoulder.

She cried out, lost her grip. Landing on her feet, she broke her fall by rolling to one side.

On the far side of the shelving, the man had quickly climbed back down to the ground. Now he began climbing directly through the shelf, kicking and knocking specimen jars and boxes aside.

Again she ran, running wildly, blindly, from aisle to aisle.

Suddenly, a vast shape rose out of the dimness before her. It was a woolly mammoth. Nora recognized it immediately: she’d been here, once before, with Puck.

But which direction was out? As she looked around, Nora realized she would never make it—the pursuer would be upon her in a matter of seconds.

Suddenly, she knew there was only one thing to do.

Reaching for the light switches at the end of the aisle, she brushed them off with a single movement, plunging the surrounding corridors once again into darkness. Quickly, she felt beneath the mammoth’s scratchy belly. There it was: a wooden lever. She tugged, and the trap door fell open.

Trying to make as little noise as possible, she climbed into the hot, stuffy belly, pulling the trapdoor up behind her.

Then she waited, inside the mammoth. The air stank of rot, dust, jerked meat, mushrooms.

She heard a rapid series of clicks. The lights came back on. A stray beam worked through a small hole in the animal’s chest: an eyehole, for the circus worker.

Nora looked out, trying to control her rapid breathing, to push away the panic that threatened to overwhelm her. The man in the derby hat stood not five feet away, back turned. Slowly, he rotated himself through 360 degrees, looking, listening intently. He was holding a strange instrument in his hands: two polished ivory handles joined by a thin, flexible steel saw with tiny serrations. It looked like some kind of dreadful antique surgical instrument. He flexed it, causing the steel wire to bend and shimmy.

His gaze came to rest on the mammoth. He took a step toward it, his face in shadow. It was as if he knew this was where she was hiding. Nora tensed, readying herself to fight to the end.

And then, just as suddenly as he’d approached, he was gone.

“Mr. Puck?” a voice was calling. “Mr. Puck, I’m here! Mr. Puck?”

It was Oscar Gibbs.

Nora waited, too terrified to move. The voice came closer and, finally, Oscar Gibbs appeared around the corner of the aisle.

“Mr. Puck? Where are you?”

With a trembling hand, Nora reached down, unlatched the trapdoor, and lowered herself out of the belly of the mammoth. Gibbs turned, jumped back, and stood there, staring at her open-mouthed.