一个名叫丽贝卡的年轻女人。她离家很多年,但回到家之后依然摆脱不了内心挥之不去的童年阴影。这个可怕的梦魇就是,她在开关灯时,眼前出现的事物总是让她难以分辨真假。她的弟弟马丁现在也遭遇了她当年所经历的恐怖事件。在恐怖现象的背后,是一个恶灵在干扰着他们的生活,丽贝卡也决定这个这个恶灵周旋到底。不过这一次,丽贝卡比任何一次都要接近真相。。Two sisters go diving at a beautiful, remote location. One of the sisters is struck by a rock, leaving her trapped 28 meters below. With dangerously low levels of oxygen and cold temperatures, it is up to her sister to fight for her life.。