Iraq, 2003. In the shadow of the Zagros mountains a military unit comes under fire from Iraqi forces. The resulting firefight causes an earth tremor where both sides fall into the ruins of a buried Sumerian temple. With all communication severed, our protagonists are trapped in a terrifying underworld they must navigate to escape - unaware that something ancient and evil has awakened in the shadows and has found a new prey to hunt.

Horrific discoveries and impossible decisions now face the survivors as they strive to escape the terrifying threat they awakened. Will they each prioritize their own survival, or put aside their fears and personal rivalries to fight together as one against these underworld monsters?