Elliot Moore: Can this really be happening?
Elliot Moore: The event must've ended before we went out today.
Mrs. Jones: Planning on stealing something?
Elliot Moore: No, ma'am, we're not.
Mrs. Jones: Plan on murdering me in my sleep?
Elliot Moore: What? No.
Train Conductor: The train service has been discountinued. This will be the last stop for all passengers.
Elliot Moore: Hey, what do you mean? Where are we?
Train Conductor: Filbert, Pennsylvania.
Elliot Moore: Filbert? Does anybody know where that is? Why are you giving me one useless piece of information at a time? What's going on? Hey, why would you just stop? You can't just leave us here.
Train Conductor: Sir, we lost contact.
Elliot Moore: With whom?
Train Conductor: Everyone.
Jared: Got kids?
Elliot Moore: No.
Jared: How come? You got... a problem?
Elliot Moore: No. She wanted to wait.
Jared: Really? For what?
Elliot Moore: For me to grow up. Why are we talking about this?
Josh: Open the door bitch.
Answer: If such an event were to actually occur in the real world, that would be the most likely scenario. The mass suicide is just how M. Night Shamylan chose to portray the event in his film.