End of the Line (2007) on Netflix

Plot summary

Karen works as a psychiatric nurse and boards the final subway train of the night. It halts in a tunnel, and she is trapped there with passengers and transit workers. Across the city a Christian doomsday cult has been handing out muffins laced with a hallucinogen, which makes anyone who eats them see demons whose eyes are flashlights. A signal sent by text message sets the cult members moving: they seize public services and start killing people they call non-believers, certain that a soul can be saved only by taking a life. Since the cult also controls the phones, television, internet and radio, nobody on the train can reach the police. Karen and the other survivors have to hold the cult off.