[From
here]
The dark looks the same, no matter what, but the moment Hime's flashlight beam ghosted over rows of books, she knew something was odd. When a flash of lightning illuminated the darkened bookstore, it was confirmed.
Somehow, they had stepped out of the institute and into Doyleton.
Hime was just about to inspect this more, to see if there was some illusion when the jingling of a bell caught her attention. It was the one on the door. The door!
"Don't let the door-" she spun around to warn Depth Charge as the man followed her inside, but before she could even finish her sentence, there was a slam and a click as the door closed behind him, seemingly by its own accord. "...close."
Now they'd done it.