The Dolls are one of the monsters seen on the whiteboard. They are bet on by the Kitchen Staff .
Physical Description
Depicted as humanoid figures wearing doll masks and black clothing, The Dolls roughly resemble a family, comprised of an older woman in a corporate suit, an older man in a business suit, a blonde pigtailed girl in a black dress, and a hooded boy. They are cruel and sadistic killers, partial to torture by fire. They are not supernatural in appearance or nature.
A mask resembling one worn by one of the monsters is seen in the cellar when Dana first enters it. It may be what summons the monster.
Appearances
The Dolls are seen in the second wave of monsters exiting the elevator during the Purge. They can also be seen in a camera view angle binding gagging Facility workers together with tape before dousing them in gasoline and setting them on fire.
Inspiration
Most likely a reference to the antagonists of The Strangers.