A massive sinkhole mysteriously opens up in Los Angeles, separating part of a family in an unexplainable primeval world, alongside a desperate group of strangers.

With Josh's life on the line, Eve traverses the dangerous wilderness back to the clearing to save him. Gavin and Izzy work to prove survivors are alive inside the sinkhole as government agents track them.

With the food supply dwindling, Eve and Ty venture into the forest on a risky hunting expedition. As an unlikely rescue mission comes to fruition, Gavin must put his faith and the fate of his family in the hands of an old friend

The sight of a crashing plane spreads a wave of unexpected hope as the survivors search for its fallen pilot. Gavin and Izzy seek help from an unlikely source after the government permanently suspends their mission.