Scary enough, right?

Well some malevolent force soon turns up to start messing with them, too.

Is there a murderer amongst them?

Or is it some sort of demonic presence?

Asked to answer a cryptic puzzle within 80 minutes, they are forbidden from leaving the room.

question when Los Angeles is devastated by a dirty bomb explosion.

Told to stay home and seal themselves off from outside air, Brads wife begins knocking on their door.

Does he let her in and risk being exposed?

Or does he keep her out, watching the consequences of those actions unfold on his own doorstep?

Elsewhere, a woman conducting the experiment starts to question their methods, and things unravel, fast.

After motels and haunted houses, gas stations are probably the most popular venues for the subgenre.

Such is the case inSplinter, which sees a young couple led there by ruthless carjackers.

But its worth every minute when a modern thriller comes out as slick and entertaining asTriangle.