London is in chaos after a military cargo plane crashes, leaving its highly classified contents strewn across the city. Completely unaware of this are four people who are trapped in the Storage 24 facility, a dark maze of endless corridors where a mystery predator is hunting them one by one.

The strangers: A couple staying at an isolated vacation home, returns from a wedding reception. They receive a knock on the door in the middle of the night. What ensues is a violent invasion by three strangers, their faces hidden behind masks. As the night goes on, the reality of their psychological terror becomes more terrifying than anything both could have imagined. Now, they must go beyond what either of them thought they were capable of in order...