The girls treat Thomas pretty well, and they make their way toward what they think is the safe haven.
Along the way, Thomas gets the girls to tell him their side of the story. They say they've been traveling through underground tunnels the whole time.
Oh, and the whole thing with Teresa kissing Thomas in the shed? It was planned—something to make Thomas trust her.
Ever since Teresa joined the girls, she's made Thomas out to be a complete monster. Everything they've done—putting him in the bag, carrying him to the camp, and so on, has been planned. The girls were also supposed to take him to a special place to kill him—but that obviously fell through.
On the second night of traveling, Thomas and the girls reach the end of the Pass and come up to a valley. It's flat, and there's absolutely nothing in front of them. There's no sign of a safe haven.
Oh, well. The girls figure they should keep moving.
All of a sudden, Thomas hears a voice. Any guesses?
Yeah, it's Teresa. She tells Thomas that the act is over and that he needs to follow her.
All of Thomas's instincts are shouting Don't! And all of us are shouting Don't! But he follows, because he's Thomas, and that's what he does.