On the far side of the other door, Karou discovered a passage of dull black stone. Peering out, she could see that the corridor went on for some ten feet before turning out of sight. Just before it did, there was a window—a narrow, barred niche at the wrong angle for her to see through from where she stood. White light washed in, painting rectangles across the floor. Moonlight, Karou thought, and she wondered what landscape she would see if she crept over and looked out. Where was this place? Like the shop’s front door, did this rear one open onto myriad cities, or was this something else altogether, some depth of Brimstone’s Elsewhere that she couldn’t begin to fathom? A few steps and she might know that, if nothing else. But did she dare?

She listened hard. There were sounds but they seemed far away, echoing calls in the night. The passage itself was silent.

So she did it. She prowled out. Quick silent steps, high on the balls of her bare feet, and she was over to the window. Peering through its heavy iron bars. Seeing what was there.

Her facial muscles, tense with anxiety, abruptly slackened with the onset of total awe, and her jaw actually dropped. It was a second before she realized it and snapped it closed, wincing when the sharp report of her teeth broke the silence. She leaned forward, taking in the scene before and below her.

Wherever this was, she was sure of one thing: It was not her world.

In the sky were two moons. That was the first thing. Two moons. Neither was full. One was a radiant half disc high overhead, the other a pale crescent just rising to clear a crust of mountain. As for the landscape they illuminated, she saw she was in a vast fortress. Huge, bermed defensive walls met at hexagonal bastions; a generous town was laid out in the center of it all, and crenellated towers—in one of which, Karou gauged by her high vantage point, she must be—reared above it all, with the silhouettes of guards pacing at their peaks. But for the moons, it might have been a fortified town of old Europe.

It was the bars that made it something else.

Extraordinarily, the city was banded over by iron bars. She’d never seen anything like it. They arched over the whole of the place from one expanse of rammed-earth walls to the next, beetle-black and ugly, enclosing even the towers. A quick study gave away no gaps; the bars were spaced so closely that no body could possibly squeeze between them. The streets and plazas of the town were entirely screened from above as if they existed within a cage, and moonlight cast rickrack shadows over everything.

What was it about? Were the bars meant to keep something in or out?

And then Karou saw a winged figure sweeping down out of the sky and she flinched, thinking she had her answer. An angel, a seraph—that was her first thought, her heart starting to hammer and her wounds to throb. But it wasn’t. It passed overhead and out of sight, and she clearly saw that its form was animal—some sort of winged deer. A chimaera? She had always supposed there must be more, though she had only ever seen her four, who would never say if there were others.

It hit her now that this whole city must be inhabited by chimaera, and that beyond its walls lay an entire world, a world with two moons, also inhabited by chimaera, and she had to grip the bars to hold herself upright as the universe seemed to tremble and grow larger around her.

There was another world.

Another world.

Of all the theories she’d dreamed up about the other door, she’d never imagined this: a world apart, complete with its own mountains, continents, moons. She was already light-headed with blood loss, and the revelation made her reel so she had to clutch at the window bars.

It was then that she heard voices. Near. And also familiar. She had listened to their murmurs all her life as their incongruous heads bent together in discussions of teeth. It was Brimstone and Twiga, and they were coming around the corner.

“Ondine has brought Thiago,” Twiga was saying.

“The fool,” Brimstone breathed. “Does he think the armies can afford the loss of him at a time like this? How many times must I tell him, a general need not fight at the front?”

“It is because of you that he knows no fear,” said Twiga, to which Brimstone only snorted, and that snort sounded dangerously close.

Karou almost panicked. Her eyes darted back to the door she had come from. She didn’t think she could reach it. Instead, she pressed herself into the window niche and held stone-still.

They passed her, near enough to touch. Karou feared that they would go into the shop and close the door behind them, trapping her in this strange place. She was ready to cry after them to prevent it, but they bypassed the door. Her panic subsided. In its wake, something else flared: anger.

Anger at the years of secrets, as if she weren’t worthy of trust or even the barest details of her own existence. Her anger made her bold, and she determined to find out more—as much as she could while she was here. This chance, she suspected, would never come again. So when Brimstone and Twiga turned into a stairwell, she followed.

They were tower stairs, a tight corkscrew down. The spiraling descent made Karou dizzy: down, around, down, around, hypnotic, until it seemed as if she were caught in a purgatory of stairs and would go down like this forever. There were small slot windows for a while, and then they disappeared. The air grew cool and still, and Karou had the impression of being belowground. She heard Brimstone and Twiga in snatches, and could make no sense of their conversation.

“We will need more incense soon.” Twiga.

“We will need more of everything. There has not been an onslaught like this in decades.” Brimstone.

“Do you think they have their eye on the city?”

“When have they not?”

“How long?” Twiga asked with a quaver. “How long can we hold them off?”

Brimstone. “I don’t know.”

And just when Karou thought she couldn’t bear any more turning, they reached the bottom. It was here that things got interesting.

Really interesting.

The stairs spilled out into a vast, echoing hall. Karou had to hold herself back to make sure Brimstone and Twiga had gone on, but when she heard their voices moving away, rendered small by the immensity of the space that swallowed them, she crept out after them.

It seemed she was in a cathedral—if, that is, the earth itself were to dream a cathedral into being over thousands of years of water weeping through stone. It was a massive natural cavern that soared overhead to a near-perfect Gothic arch. Stalagmites as old as the world were carved into pillars in the shapes of beasts, and candelabras hung so high they were like clusters of stars. A scent was heavy in the air, herbs and sulfur, and smoke wreathed among the pillars, teased into wisps by breezes emanating from unseen openings in the carven walls.

And below it all, where Brimstone and Twiga walked down the cathedral’s long nave, there weren’t pews for worship, but tables—stone tables huge as menhirs, so huge they must have required elephants to haul them there. Indeed, they were large enough to accommodate an elephant reclining, though only one of them actually did.

An elephant, laid out on a table.

Or… no. It was not an elephant. With clawed feet and a head that was some nightmare of a massive, tusked grizzly bear, it was elsething. Chimaera.

And it was dead.

On each of the tables lay a dead chimaera, and there were dozens of them. Dozens. Karou’s gaze fluttered, erratic, from table to table. No two of the dead were alike. Most had some human quality to them, head or torso, but not all. There, an ape with the mane of a lion; an iguana-thing so huge it could only be called a dragon; a jaguar’s head on the nude body of a woman.