My front-door key didn’t fit the lock. No surprise there, not after so much time. Even a lethargic landlord changes the locks every few years. I used to be able to slip the old one with a credit card, but this one seemed to be made of sterner stuff. I rang a couple of bells – Patel, for one, and someone named Gilbey – and somebody buzzed me in and I climbed four flights of stairs. That wasn’t any easier than it had ever been, but it wasn’t noticeably harder, either, and I suppose that was something to be thankful for.

My name was still on the bell. I pondered that fact as I climbed the stairs. I still lived here, but how could that be?

A doppelganger, I thought. A sixty-four-year-old Evan Tanner, padding around in a moth-eaten cardigan and carpet slippers, writing cranky letters to cranks all over the world, making coffee in my kitchen and sleeping in my bed. And what would happen if we crossed paths? Would one of us vanish in a puff of smoke? If so, which one would it be? Or would we cancel each other out like positive and negative charges, both simultaneously ceasing to exist?

I know it sounds far-fetched. But the whole day had been far-fetched from the moment I opened my eyes, and it wasn’t growing ever more plausible with the passage of time. It was only the persistent chill deep in my bones that let me believe I really had been in the deep freeze. If I could swallow that particular camel, why strain at a doppelganger?

I mounted the last step, walked the length of the hallway, and stood in front of my own door. The nameplate beside the doorbell held my name, but I didn’t ring the bell, nor did I knock on the door. I just stood there for a long moment, listening but not hearing anything, and then I tried my key in the lock, and it turned. I pushed the door open and walked on in.

It was still my apartment.

Oh, it was different. The walls had been painted – probably more than once – and there were different pictures hanging on them. Some of the furniture was new, but some of it was the same as it had been when I left it. And the floor-to-ceiling bookshelves which I’d installed in every room were there still, and I recognized my books on the shelves.