Don’t Hang Up (2016)

Following a long tradition of cocky teenage boys with too much time on their hands, Brady, Sam, ​and Mosley like to amuse themselves by making prank calls. However, their cellular diversions are intensified by the extreme nature of the pranks they put their unsuspecting victims through and the delight and encouragement they receive when they post videos of their hijinks online for maximum humiliation. Having pushed the wrong person too far, they find themselves on the other side of a call, and an evening intended for normal high school revelry turns increasingly bloody as their unknown assailant ramps up a prank of his own.