All I know is, when I walked in the front door of Katherine’s new house, I was already walking back out again. One second I was facing the doorway, stepping across the uneven, unpainted porch—the next I was walking back the exact same way.

It was a doorway with only one side, like a goddamn Möbius strip. Since this is flat-out impossible, my brain found excuses. “I’m just disoriented,” I thought. “I’m pacing without realizing it.”

Hell, it took me three tries before I realized something funny was going on. I guess I had other things on my mind. I must have looked like an idiot, stopping, peering at the doorway, running down the porch steps, grabbing a stick, running back.

I tossed the stick through the doorway. It landed at my feet.

Birds chirped. A breeze picked up and died away.

I pulled out the manila envelope I’d been carrying. There was writing on it—blocky, Cyrillic capitals. I couldn’t read Russian, but I knew what it meant.

One way or another, I had to get in there.