In the middle of a routine patrol, officer Daniel Carter happens upon a blood-soaked figure limping down a deserted stretch of road. He rushes the young man to a nearby rural hospital staffed by a skeleton crew, only to discover that patients and personnel are transforming into something inhuman. As the horror intensifies, Carter leads the other survivors on a hellish voyage into the subterranean depths of the hospital in a desperate bid to end the nightmare before it's too late.
When Heather and Sarah Ann were growing up they told each other every secret. But Heather left their small town on the last day of high school vowing never to return. Forced to come back when her father becomes ill, the young documentary filmmaker is pressured into filming Sarah Ann's wedding video. Heather is convinced that the edgy filmmaker and bubbly pink-wearing bride have nothing in common, but as the big day approaches she finds that no one is quite what they seem – especially the old friend she thought she knew better than anyone.
