The barriers are the obstacles that stop the seven strangers from leaving The Town.
So far, the barriers are as follows:
- An implant in the leg of each stranger that releases a knockout drug into the bloodstream. These implants are removed by Moira Doherty in the beginning of "The Edge".
- The second barrier, first seen in The Edge, is an ADS or Active Denial System, which uses microwaves to burn skin. Janet runs full-speed into this barrier, and suffers mildly painful burns on her face. Later, McNair determines that they surround the entire town.
- The third barrier is a mysterious bright light that manages to turn the van (Stolen from the Asian cooks) around, or teleport it back to the edge of the town. (The Edge)
- A fourth barrier is a steel wall, underground, that blocks the stranger's escape tunnel. By hammering on the barrier, a vent opened up as an alarm sounded and released a white gas, which incapacitated Janet Cooper.