The cat at Central Library is named Dewey, because of course he is, and nobody remembers adopting him.

He is black all the way through, except for his eyes, which are the gold of a reading lamp left on in an empty room. He sleeps on the warm sill above the returns slot. He walks the stacks at closing with the slow authority of a docent. Patrons who have been coming for twenty years swear he has always been exactly this size.

The children's librarian keeps a notebook of the things Dewey stares at.

Not people. Dewey has no interest in people, except as furniture that occasionally holds tuna. What he watches is a spot just behind people, and slightly above, about where a second head would be if someone were standing very close and very tall. He fixes it with total attention, ears forward. Then, satisfied, he looks away.

The notebook goes back years. Most entries are short:

Behind the man reading Fiskadoro. Long stare. Purred.

Behind the girl doing her taxes. Hissed, once. She got a refund.

Behind me. Eleven seconds. Then he licked his paw like it was nothing. It was not nothing.

In October, the stares get longer.

Mina, who closes on Thursdays, started timing them with her phone. In September the average was four seconds. By the third week of October it was nineteen. On the night of the twenty-ninth, Dewey sat at the top of the grand staircase and stared at the empty air above the atrium for four minutes and twelve seconds, and the escalators, which had been switched off since six, began to run. Only the up one. Only for him.

He did not ride it. He watched it, the way you watch someone you love get on a train.

When it stopped he went downstairs, past the reading porch and the closed café, to the sub-basement door that is supposed to be locked. He sat in front of it. Mina, who is a professional and does not believe in anything, opened it for him.

On the tiles inside, where the floor is patterned in old red and blue squares, someone had arranged pecan shells into a spiral. At its center was a single lantern tag, stamped 037.

Dewey sniffed the tag, sneezed, and walked out the other way, through the window of a narrow white house that Mina would have sworn was not there that afternoon.

He was back on the returns sill by morning, asleep, gold eyes shut. The notebook entry for that night reads, in its entirety:

He's not looking behind us. He's looking at who is about to arrive.