A young newlywed couple find themselves trapped in a network of underground caves. With her husband injured, the new bride is forced to find her way back to the surface in order to save his life. In the process, they discover a terrifying truth about the "underneath", they are not alone. Something evil is hunting them.。一颗子弹,三条命,每个人都将付出代价。洛杉矶的一天,墙内的青少年正在欲购买非法枪支,墙外一对即将离婚的夫妇正在为离婚条件争执,枪支意外走火,射中了路过的丈夫。此时,他们的生活正将发生翻天覆地的变化。。