At 'simulation', at 'test', Morgan's shock shows on her face. You can know something with utter certainty, with all the proof-from-experience in the world, but if everyone around you -- even the ones who aren't acting, even the ones who acknowledge that this town is a sealed bubble full of lies -- if everyone around you has other ideas, then even if you don't doubt, you can start to feel mad. Morgan didn't doubt, but she's nevertheless struck silly by the fact that Renee knows.

(She doesn't suspect at all that they're using 'simulation' to mean two distinctly different things.)

"It is," she confirms, "it- it is. I haven't been able to even find the walls; it's bigger in scale than--" her apartment "--any simulation I knew about before." And worse somehow, because she has reason to suspect that Alex isn't in charge of her captivity any more, and she thinks she knows exactly why--

"How did you learn--" She breaks off for another furtive look around, at the windows of the house, at the darkening street, at the sky. The seams of the sky are imperceptible, but that's technology for you. She's not yet been able to throw something high enough to hit it.