When a massive sinkhole opens in the middle of Los Angeles, pulling hundreds of people and buildings into its depths. Those who fell in find themselves in a mysterious and dangerous primeval land, where they have no choice but to band together to survive. Meanwhile, the rest of the world desperately seeks to understand what happened. In the search for answers, one family torn apart by this disaster will have to unlock the secrets of this inexplicable event to find a way back to each other.

After a cyber-bullying incident results in a brutal murder, the shocking violence stirs up memories of a killing spree from the past that has haunted some, intrigued others and maybe just inspired a new killer. A group of teens - with two old friends struggling to reconnect at its heart - become lovers, enemies, suspects, targets and victims of an assassin who's out for blood.