It didn’t confuse her, but it might have pissed her off, because Quentin barely made it to the stairs before she banished the illusion so harshly that he felt like somebody had scrubbed his brain with steel wool. Go on or go back? In an undignified panic he feinted for the stairs, dodged past Alice at close quarters, arching his body like a bullfighter, and locked himself in the half bathroom off the landing.

Now he’d trapped himself, but good. He fumbled in his pocket and whipped out a Sharpie he’d been keeping on him in case of emergency. Scribbling at top speed he wrote an inscription in Swahili across the door, then sketched a big rectangle around the whole frame, with fiddly ornaments at the corners, all executed in one unbroken line. It was just a ward to insulate against magic, because, he reasoned hopefully, Alice was made of magic now. It was all he could think of.

The door shook with an impact, bulged visibly inward, air puffing in around the edges as if a grenade had gone off behind it. It held, but immediately it began warping in its frame, and the paint started to blister. It wasn’t going to hold for long. It wasn’t meant to be a magic barrier, it just wanted to be a bathroom door.

He turned around and his eye fell on the medicine-cabinet mirror, in which it continued to snow. Experimentally he put a hand through it—no resistance. Another portal. He put one foot on the toilet, planted his knee on the sink and fed himself through the narrow opening.

It was cold in the other bathroom—the other-other bathroom. He crawled desperately down off the sink and half fell onto the bathroom floor, which was slick with slush. Where was he now? Two worlds removed from reality now, a land within a land. Another level down.

What would he do when the door failed? He might be able to slip past her again, get back through, but then what had he gained? He didn’t want to leave empty-handed, not again. This free diver was going to touch bottom, even if it meant he wasn’t coming back up. There must be something interesting down here. At this depth maybe some of the rules would start breaking down.

Slipping and sliding to his feet, he half walked, half skated out into the hall and into the mirror-image of the mirror-image of the workroom. The lights were out in this one, and he hastily summoned some illumination—the palms of his hands glowed like flashlights. Something was different here. He could almost feel the increased pressure of the multiple layers of reality above him. This land was heavier somehow: like it had been put through a photo filter that saturated the colors and made the black lines thicker and darker. It tried to push into his eyes and ears. He couldn’t stay here long.