Once you go in, you don’t come back.
A biologist joins a military expedition into the Shimmer, an expanding zone around a coastal lighthouse where physics and DNA refract into each other. Every team sent in has vanished; her husband came back wrong.
We return to the opening scene where Lena is being interviewed by Lomax. Lomax tells Lena that when The Shimmer burned, Kane came out of the coma. Lena goes to his room, where Kane is sitting up on the bed. They look at each other, and Lena asks if he’s the real Kane. He says he doesn’t think so. They embrace, and we see something moving in Kane’s eyes…then in Lena’s.