"Fifteen?" his cellmate asked, suddenly sounding excited.
"Why? What does that mean?"
"You don't know?"
"Know what?"
"Fifteen, you're the one. You did it. You escaped."
"Escaped? What are you talking about? I didn't escape anywhere. I told you. I don't know how I got here or even where here is. The last thing I remember was going to bed in my apartment. The next thing I knew ..."
"Your apartment? I think you might be missing some memories. The newest fabricated memory you should have is leaving Earth and coming to this planet. Maybe you bumped your head. You weren't in any tight spaces recently, were you?"
The tunnel. Fifteen (apparently that was his name, or rather designation) finally realized why he must have been in that tunnel. He climbed in there to escape, thinking that it led somewhere. Then he must have bumped his head, knocking himself out. So he really did have amnesia. Sort of.
But what exactly was Fifteen escaping from?
"Tell me," he asked Fourteen. "Why was I escaping? I can't remember."