The first time he saw it, Isaac Skinner was transfixed by the ceiling of the Catacomb Theater.

It was painted with an elaborate fresco, rich in details and livid red in color. Gilded lines shone like embers in a masterful depiction of the nine circles of Hell.

He spent a few minutes craning his neck, picking out the shapes of tormented figures in the red haze. The illusion of depth made the ceiling seem like a pit, bright around the edges and fading to black near the center.

Finally he pulled his focus back down, onto the carpeted aisle and the gleaming main stage. Most of the cast was already there.

To Isaac’s surprise, they were all wearing half-masks. He could not recognize anyone but Victor Belka, who smiled as Isaac approached.

“Glad to see you made it.” As always, Victor’s voice was smooth, faintly condescending and inexplicably sad. “You were almost late.”

“Why all the masks?” Isaac asked.

“Theatrical masks are as old as theater itself. I’ve always wanted to try a masked production of Hamlet. It seems fitting, given the secrets each character conceals. None of them are truly forthright—except Horatio, of course.”

Victor pointed to Horatio standing near the back of the stage. His face was unmasked, ruddy and oddly out of place.

“Interesting choice,” Isaac said, though he found it bizarre. He’d learned quickly not to argue with directors. “I guess it’s all Horatio’s story, in the end.”

“If only because he lived to tell it,” Victor agreed. “Here.”

He offered Isaac a plain white half-mask, sharp and angular and ending abruptly at the bottom of the nose.

When Isaac strapped it over his face, he was surprised at how light it felt. Behind the disguise, with his eyes peering out through rounded holes, he felt invisible.

“There’s also the psychological benefit of anonymity,” Victor said, glancing at Isaac’s unreadable expression. “Actors in masks typically feel less restrained.” He raised his voice. “Five minutes, and then we’ll take it from the top. Act one, scene one, please.”

The cast began to disperse. Some of them chose seats in the empty auditorium, while others disappeared into the wings. Isaac followed the latter group. He enjoyed the unique perspective offered behind the curtain—a narrow sliver of stage, seen from an angle the audience would never experience. He liked the camaraderie and the warm smell of sawdust.

As the rest of the cast chattered in low voices that were not quite whispers, Horatio and Marcellus went stomping onto the stage. Isaac watched them with some amusement as they bickered over the ghost.

The ghost himself was a tall man in a pale, ethereal blue mask. As he stalked across the room, the guards drew back in terror, but Horatio stepped forth boldly.

“Stay!” he commanded. “I charge thee, speak!”

The ghost wavered for a moment, and in his reluctance Isaac felt he was on the verge of words, but in the end he simply drifted away into the curtains.

When the first scene was finished, they skipped straight to the fourth, since it had the same setting and nearly all the same actors. Isaac joined Marcellus and Horatio on the stage, where the spotlights were hot against his skin. Victor watched them silently from his seat in the front row. All Isaac could make out were his eyes, glittering in the dim house lights.

Marcellus’s actor had not yet memorized his part, so he clutched a ratty script in one hand and glanced at it while he spoke. His delivery was stilted, and it threw Isaac off.

But Horatio spoke his lines perfectly, with just enough weight. Isaac could bounce off them easily, pulling Hamlet’s bitter uneasiness into his voice. He could almost feel the nipping cold.

When Horatio called fearfully, “Look, my lord, it comes!” Isaac turned to face the ghost.

He was ready to be afraid. Angels and ministers of grace defend us! waited on the tip of his tongue. And yet fear, real fear, caught him so utterly off-guard that he froze, unable to move or speak or even breathe.

A ghost stood on the stage.

Isaac did not believe in ghosts, but he knew death when he saw it. The figure was a pale, translucent gray, the color of ash. Dark flecks swirled behind his transparent skin. His face was hidden behind a frowning mask, and on his head he wore a crown.

Isaac inhaled sharply. He could smell seawater, and hear the shrieks of distant gulls. Fog rolled over the stage, obscuring the auditorium and the other actors in a soft veil.

The apparition’s hands were bound behind his back. Long chains trailed behind him, snaking over the stage and vanishing in the mist.

Isaac met the dark eyes behind the mask and saw, with perfect clarity, madness reflected back.

The urge to run was overwhelming. He stumbled backward and his foot caught the edge of the stage, making a terribly loud sound.

The ghost’s head snapped toward him.

The rapid motion, and the alien intent behind it, sent Isaac scrambling over the edge. He fled down the aisle, heedless of the strange sounds behind him, dreading the touch of icy fingers on his back.

***

Isaac left the Institute before anyone could stop him, with no delays and no detours. Even in the light of the afternoon sun, speeding down the highway, surrounded by shades of dull brown, he could feel his heartbeat pulsing in his teeth.

If he’d imagined the ghost—and the crocodile, and the song—he was delusional.

If they were all real, that was even worse, because the world was delusional. Dead men walked the streets. Beasts prowled the waters. Isaac did not understand any of it.

While he drove blindly away from SEIDR, with his hands strangling the steering wheel, everything blended into a single shuddering blur. His breath came in short, frantic gasps. The sun winked at him in the side view mirror.

He was unreasonably surprised when a siren started behind him. A very different type of unease settled in his stomach as he caught a glimpse of the flashing red and blue lights.

Isaac pulled over on the wide, dusty sideburn of the highway. The police car trundled up behind him. When he rolled down his window, the dry winter air swept in, chilling his fingers.

The cop was a slouching, weatherbeaten man. He strolled up to Isaac’s car and said, “Take off the mask, sir.”

Isaac reached up and pulled off his mask. He hadn’t even realized he was still wearing it.

“Know how fast you were going?”

“No.”

“Care to take a guess?”

“No.”

“Pretty damn fast, I’d say.”

Isaac fastened his eyes on the horizon and said nothing.

The cop licked his lips. “What’s got you in such a hurry?”

“Nothing important.”

“I saw you driving down from that big old theater, just a few miles back.”

“I just got off work,” Isaac said.

The cop gave him a short, dusty chuckle. “So you’re just racing to get home. Is that it?”

“That’s exactly it.”

“Huh.” He took a step back from the car, scanning the foothills. “Somehow, I don’t find that likely.”

“Are you going to give me a ticket or not?” Isaac asked, slivers of impatience prickling under his skin.

“What’s got you all spooked?” the cop said abruptly.

“What?”

“I’d have to be stupid to miss it. You see something scary in there? Something unnatural?”

Isaac did not reply.

“Everybody knows there’s something weird going on up there,” the cop said. “They got all sorts of screwy people coming and going. Morning, noon and night. But I never seen one in such a hurry to leave before.”

“I don’t know what you’re talking about.”

“No, I’m pretty sure you do. Even if you don’t wanna spill it.”

Isaac bit his lip, resisting the urge to say something divinely foolish.

The cop rapped his knuckles against the roof. “Drive carefully.”

***

When Isaac finally reached his house, he was shaking. The whole day lay on him like a fever, smothering all rational thought in sweltering fear.

He parked the car in his driveway and went trudging through the trees, over the frozen creek, and into Basil’s backyard.

On his way to the front door, he passed through his uncle’s apiary. Beehives stood like obelisks, white snow-covered mounds. He walked between them, where the air pulsed in a low, endless buzzing.

Basil opened the door with a broadening smile. He was wearing fuzzy green slippers and a pair of reading glasses. “Isaac! What a pleasant surprise. Please, come in.”

Isaac took his customary seat at the kitchen counter while Basil pulled two mugs from the cupboards. “What kind of tea?”

“Something green.”

“Are you alright?”

“Fine,” Isaac said. “You?”

As Basil boiled the water and spoke of slow, quiet days, Isaac felt his tension gradually drain away. In its place there was a gathering silence, a nothing space.

When the tea was ready, Basil handed Isaac his cup. It was an old red mug, battered and chipped, with a line of metallic silver encircling the middle. Isaac clutched it with both hands, feeling the warmth seeping through the clay.

“I went back to Oshun,” he said.

Basil’s bushy eyebrows shot up. “And?”

“It was a mess,” Isaac said, and then he was spilling everything, from the Wizards Guild to the voyage itself to the dreadful wreck of the Rambler. Basil listened carefully, tilting his head and asking no questions until Isaac was finished.

“I must say,” he finally offered, staring into his own tea, “it sounds like SEIDR has not changed much.”

Isaac laughed without humor. “Can’t say I’m surprised.”

“Do you know if Osmund was still working aboard the Rambler?” Basil asked, with his eyebrows drawn.

Isaac’s throat hitched. The name sounded uncomfortably familiar. “Spelder might have mentioned him. I think he died when the ship was attacked. Did you know him?”

“A long time ago, yes,” Basil said softly. “He was … a friend of a friend, I might say. A kind man.”

Isaac frowned. “I’m sorry.”

“So am I.”

“They lost someone else, in the isthmus.” Isaac took a sip of tea and winced. It was still far too hot. “Or that’s what they think happened, anyway. They don’t know who it was.”

“Of course.” His uncle sighed heavily. “It is a terrible thing to hear, all the same.”

“Do you know how many people die working for SEIDR?” It was something Isaac had been thinking about, in the back of his mind, ever since the Ceremony of Remembrance. He remembered signing plenty of disclaimers and waivers, but no precise statistics.

“They do not release those numbers.” Basil rubbed his nose. “Though I am sure they keep careful records.”

“I guess they’re worried they might scare people off,” Isaac muttered. At once, he imagined all the souls who crawled down into SEIDR’s caves and never came out. If ghosts were real, the Institute would be teeming with them.

But Isaac did not believe in ghosts, so he clenched his teeth and asked, “Uncle, have you ever seen anything that wasn’t … really there?” He took a sip of tea to hide his expression, and then quickly clarified, “In SEIDR, I mean.”

Basil looked more thoughtful than concerned. Isaac took that as a good sign. “Once, when I was alone in the tunnels, I saw a small fox just ahead of me. I followed it for quite a while, but eventually it disappeared in the dark. I could never be sure if I imagined it.”

Isaac smiled. Of course, a small fox sounded much more pleasant than the creatures haunting his own skull. “I don’t think a fox could take the elevator down without someone noticing.”

“But there are more ways into SEIDR than the elevators alone.”

Isaac crossed his arms. “Really?”

“The caves are much larger than the Institute itself. No one knows exactly where they end. It is not unlikely that some hole in the desert might cross paths with SEIDR’s warrens.”

“So it was a real fox that wandered into the tunnels.”

“I believe so, yes. It moved like one.”

Isaac felt oddly disappointed. It seemed he was the only one imagining ghosts.

Now that he’d recovered from the initial burst of shock, he was starting to regret running. In the end, he was only delaying the inevitable. He had to return to SEIDR, sooner or later, if only to figure out the truth of what he was seeing.

“Why do you ask?” Basil asked.

“Curiosity, mainly.” Isaac scrambled to change the topic. “I finally visited the New Frog Chess Club, by the way.”

“Oh? And what did you think?”

“I liked all the frogs,” Isaac said. “I also got the distinct impression that something very fishy was going on.”

“What do you mean?” Basil’s voice was just a little too incredulous.

Isaac pulled Harley’s card from his pocket and passed it to Basil. “It says break the first rule on the back. Does that mean anything to you?”

Basil’s frown was exaggerated and unconvincing. “Nothing. They may have changed in the many years I have been gone.”

“Sure,” Isaac said, frowning back at his uncle. He knew Basil well enough to realize when he was lying. “Could you at least give me a hint?”

Basil handed the card back to Isaac. “Member meetings are on Saturdays.”

“That’s what Harley said,” Isaac snapped. “But I’m not a member yet, am I?”

“You may want to work on that.”

“How?”

“Excellent question.” Basil smiled. “If I were you, I would start by breaking the first rule.”

***

Isaac left in a flustered hurry. Something had clicked in his brain and he wanted to chase it down before the uncertainty drove him insane.

He took the elevator down to SEIDR’s lobby. His feet ate up the winding route to the shipyard while his mind mulled over foxes and tunnels and secret caves in the desert.

To his tremendous relief, he spotted Harley as soon as he stepped into New Frog Chess Club. She was watching an intense match and chatting with a few of the other spectators.

She looked up and spotted Isaac. A slow smile crossed her face. “Welcome back.”

“Can I talk to you?”

“Go ahead.”

“Alone?”

“Oh. Yeah.” Harley tore her eyes away from the game. “Let’s go upstairs.”

Isaac followed her up the narrow staircase to the third floor. The roof was low and sloping, matching the contours of the frog. Bare light bulbs hung from the ceiling. There were a number of small booths surrounding a central bar.

Harley slid into one of them and Isaac sat down across from her. A faded chess board was painted on the tabletop.

“What’s up?” Harley asked.

The seats were covered in peeling red vinyl. Isaac resisted the urge to pick at it. “What’s the first rule?”

She blinked. “Of what?”

“Don’t tell me you didn’t write this,” Isaac said, pulling out the card.

Harley gave it a scornful look. “Course I did. It’s self-explanatory.”

“It hasn’t explained much.”

“So?”

Isaac hesitated. “So I was hoping you might be able to help me out.”

“Sorry. Can’t.”

“Seriously?”

“Not with that.” Harley shrugged. “Temur’s here, by the way, if you wanted some training before your chess match.”

“What chess ma—oh.” In all the madness and mystery, Isaac had almost forgotten his game against Miriam. Remembering carried a sick swell of nausea. He still didn’t know how to play chess. “Well. That’s good. I’ll need all the training I can get.”

“Great. I’ll let him know.” She got up a little too quickly.

Isaac was left with the sinking sensation that Harley was lying. And yet as much as he wanted to, he couldn’t figure out what odd secret she and Basil had in common—or why they refused to share it.

Harley returned with Temur Atabay in tow. He was a wispy man with a long mustache and an old-fashioned waistcoat, though Isaac guessed he wasn’t much older than twenty.

“You must be Isaac,” Temur said, giving him a bone-rattling handshake. “Am I to understand that you need to win a game against Miriam Oleander?”

“Correct,” Isaac said.

“Well, I’m afraid it’s never going to happen,” Temur said. “Sorry.”

“Come on. It’s not impossible.” Harley elbowed Temur. “I’ve seen her lose before.”

“Not under these circumstances.”

“Gray beat her sixteen times in a row,” Harley said, unexpectedly quiet, and Isaac’s ears pricked up.

“He’s no Gray.” Temur glanced at Isaac. “Well, no offense. But you’re no Gray.”

“She was good?” he asked casually.

“The best.” Harley drifted toward the stairs. “Luckily, you don’t need to beat her. Just Miriam.”

Temur started to protest, but Harley was already gone. “Just Miriam!” he said, shaking his head. “Just Miriam could win six out of seven games against anyone here. I’m sorry, uh, Isaac, but it’s not looking good.”

“I’m still willing to try,” Isaac said stoutly, as if mere determination could carry him to victory.

“Well, I brought pieces,” Temur said, emptying his bag onto the table. “We can start with the basics, but I don’t want you to get your hopes up.”

There were too many basics, in Isaac’s opinion. He couldn’t keep them all in his head.

Oh, the moves were simple enough, but the sheer quantity of openings boggled the mind. Every new piece of advice seemed to wipe the previous one from existence. After twenty minutes of enthusiastic demonstrations, Temur reset the board and said it was time for a real game, but Isaac knew even less about chess than he’d started with.

So they played a real game. Isaac watched Temur’s mustache droop lower and lower with every turn, until finally he asked, “What’s your rationale here?”

“For the move?”

“Yes. What are you trying to do?”

Isaac studied his knight, which he’d planted squarely in the middle of the board, threatening Temur’s queen. “I don’t know. I wanted to see what you would do, I guess.”

“Well, I would probably do this.” Temur slid his queen forward. “And that’s checkmate.”

“Ah.” Isaac stared at the board until the squares blurred together. “I’m not going to beat Miriam.”

“I would be very surprised if you did,” Temur said diplomatically.

“Is there anything that might give me a chance?” Isaac’s voice was pleading. “Any secrets? Any tricks that might catch her off-guard?”

“There aren’t many secrets in chess.” Temur tapped the board. “For the most part, what you see is what you get. And if there were any tricks that might grant you an advantage, well, Miriam would already know all about them.”

“I suppose she would.” Isaac sighed. “Can we play again?”

***

Isaac left the New Frog Chess Club a hopeless man.

Winning against Miriam would be impossible. There were no shortcuts. He’d imagined studying the game would give him a better chance, but it only served to highlight how much he still didn’t know. He’d trapped himself, once again, in a perfect quandary.

As he meandered away from the shipyard, his head bowed in remorse, he wandered further and further into the snaking tunnels of SEIDR.

The lanterns were hung infrequently, bright spots of gold to break up the pitiless dark. Isaac enjoyed the space between the lanterns—where he walked, shadowed and unseen, and yet the light glimmered just ahead—where his past and future were starkly illuminated, and only the present was a mystery. It was the exact opposite of how he felt.

He was only faintly aware of the time and space he inhabited. Most of his thoughts were spent on other thoughts, a circular process of rediscovering and reforgetting the same problems over and over.

It was only the unexpected sight of another person in the distance that dragged him out of recollection and into his wandering body.

The figure was still distant, approaching at a steady pace, rendered only in vague silhouette by the golden lights.

Isaac had not seen anyone else in a while. A suggestion of fear prickled across his skin.

There were no branching paths or intersections along this stretch of the tunnel. Isaac had exactly three options: go backward, go forward, or stay where he was.

He wanted to keep walking, but some part of him urged caution, so he stopped in the next span of shadow. From here, he watched as the stranger drew closer and closer, until finally Isaac could see his face clearly.

And now Isaac was utterly astonished, for Victor Belka was just about the last person he’d expected to find here.

The director stopped under the nearest lantern. “Hello, Isaac. Care to join me in the light?”

Isaac stepped forward into the lantern’s glow, speechlessly baffled. The director’s tone was casual, as if the two of them had arranged a meeting here on purpose.

“I must say, your performance this morning was rather concerning,” Victor said. “Not the acting itself, of course. That was excellent, but the running was rather unorthodox.” His unspoken question hung like gossamer on the air.

Isaac’s ears burned. His fear of the ghost seemed flimsy, now, compared to the embarrassment of sprinting off the stage. “I’m sorry. That doesn’t usually happen.”

“I should hope not. I was worried you might have quit.”

“No,” Isaac said quickly. “I’ll be at the next rehearsal. I don’t plan on running away again.”

Victor smiled. “Try not to make a habit of it. People might start asking questions.”

Desperate for a change of topic, Isaac asked, “What are you doing here?”

“When I can’t solve a problem, I like to walk. It helps me consider a situation from every angle.”

“What kind of problem?”

“A doppelganger problem,” Victor said. “One that we happen to share.”

“Ah.”

“What are you doing here, Isaac?”

Isaac scratched the back of his neck. “The same thing, I guess. Walking and thinking about problems.” Between Hamlet and the ghost, Caasi and the cloak, and his doomed chess match with Miriam, he was feeling a little short on solutions.

“Well, you’re a long way from the shipyard. Clearly you don’t have your answers yet.” Victor met his eyes. “What’s troubling you?”

From the variety of options in his head, Isaac plucked a single stray thought which had been worrying him for a while. “You want me to catch Caasi.”

“I do.”

“But he has a cloak of reality.” The words stung Isaac’s lips with the faint memory of betrayal. “I read all the files you gave me. I’ve seen him appear and disappear like smoke. I know how it works, more or less.”

“I’m glad you’ve been doing your research.” Victor’s face was severe, but his voice was cheerful.

“But I still can’t figure out how to catch him.” Isaac’s fingers clenched around the edges of his sleeves. “I know he’s interested in Mu, but I don’t see the point of chasing him around. As long as he’s got the cloak, he can go anywhere.”

“If I might offer a word of advice,” Victor said lazily, “you should try separating him from that cloak.”

“Easier said than done.” Isaac leaned against the wall. He hadn’t noticed how tired he was until now. “Caasi’s dangerous. He killed Jon Sprenger just for being there. He tried to kill Felix for no reason at all. If anyone gets close enough to touch him, their life is already at risk.”

“It would certainly be difficult,” Victor admitted. “But not impossible.”

“I just don’t see the point of chasing him unless I know how to stop him.” Isaac rubbed his eyes. “It would be a lot easier if he wasn’t invincible.”

“Not quite invincible.”

“Close enough. We can’t hurt him, can we?”

“Not through any conventional means,” Victor murmured. “So far as we know, there is only one way to kill a doppelganger.”

Isaac’s hair stood on end. He knew, of course; he’d read Silas’s file, and examined the grisly photos. But now, hearing it from Victor in this empty, distant corridor, the implications finally sank in.

“How?” he whispered.

Victor winked. “Killing their counterpart, of course.”

The gears in Isaac’s head started turning. “So if I can’t figure out a way to catch Caasi—”

“Oh, you will,” Victor said. “I have absolutely no doubt about it.” The yellow lantern over his head twirled slowly, sending black slats of shadow spinning over the walls. “After all, you have no alternative.”