在不久的将来，只需拨打一个电话就可以阻止犯罪和事故。然而，这个乌托邦世界的和平将被一名有条不紊的杀手所破坏，他似乎发现了这个系统的唯一缺陷。

In a near future, crimes and accidents can be prevented by making just one phone call to the past. However, the peace of this utopian world will be di