1X06 His Sister's Keeper (Finn)
There's this feeling, in the pit of your stomach, like something's wrong, like something's off. You keep thinking about the grounder, how he moved slow and steady through the woods, and how he never seemed to notice your group following him. You creep into his hideout, and you can't help but think that he led you here.
Your suspicion only intensifies when you find the foghorn looped from his belt, and realize that it was him, he called the others off, you've just got no idea why.
You don't see his eyes snap open, but you do feel the knife.