The lightning resumed. Cora squeaked, not quite a gasp and not quite a scream, but something small and shrill and laughable. Christopher wasn’t laughing. He was watching as the lightning came down faster and faster, forming crackling chains of light. There was something behind that light, something buried in the brightness, something clean and old and unfamiliar, something—

With a final great sheet of blue-white brilliance, the lightning stopped again. The air, still heavy with ozone, pulsed under the weight of what it had just birthed.

And there, in the center of the room, atop the blackened concrete, was a door.

It would have been an ordinary door if it hadn’t been standing where no door was normally found, where no wall was present to support it. Christopher slid shakily off the bed and stood, keeping his eyes on the door the whole time.

“Cora?” he called. “You see this?”

“It’s a door.” She finished making her way down the stairs, clutching the bannister, hair still bushed-out and frizzy. “There isn’t usually a door there.”

“I think I would have noticed, yeah.”

“Is it…?” The question died on her lips, like she was afraid speaking her suspicions out loud would stop them from being true.

Christopher shook his head. “No. My door didn’t—I mean, Mariposa isn’t big on lightning. The Country of Bones runs on a different kind of power. This isn’t my door. Is it yours?”

“I didn’t have a door.” Cora moved toward him with exquisite care, skirting the char marks on the floor. Sometimes it surprised him how delicately she could move. She was a large, round glory of a girl, and between her size and her hair, it seemed like she should take up more space than she actually did. “I had a patch of waterweeds and a pattern of light on the water. Miss Eleanor says that’s pretty common for submerged worlds. Wood rots, steel rusts, but abstract concepts remain.”

“Sometimes all this gives me a headache,” said Christopher. He took a cautious step toward the door. It stayed where it was, apparently solid, and didn’t burst into flames, or strike him with a bolt of electricity, or anything else unfriendly.

“Do you want me to get Kade?”

Christopher hesitated. Kade was Eleanor’s nephew and recognized second-in-command: when something didn’t necessarily need the attention of the headmistress, it was Kade who made everything work. But classes had ended hours ago, and he was probably upstairs in the attic, working on his own projects. He didn’t get much time to himself, what with the little problems that cropped up during the day and managing the school’s shared wardrobe.

“No,” said Christopher slowly. “I don’t want to bother him just yet.”

Cora eyed him. “It’s a door.”

“I can see that.”

“Most of this school is waiting for a door.”

“I am aware.”

“So don’t you think—”