Ava Brown, a newly employed security guard at Rooger, a Tech company, is doing the rounds when a deafening sound hits her and she falls in tremor. Alongside her colleague, Richard, they decide to investigate the source together. They take the elevator to the first floor, but it comes to an abrupt halt on the third, as a blackout occurred.
After hours of futile waiting, the co-workers decide to climb up the shaft and what they see outside the building makes their blood run cold. Ava goes on the move to find her daughter, with Christopher tagging along.
They navigate through the chilly darkness, encountering petrified people and creatures of all kinds, including a terrifying, glowing oval-shaped creature. Resistance is futile and communication is impossible.
Misfortune strikes again, and Ava loses her companion. Alone and haunted by terrifying darkness, would she be valiant enough to succeed on her mission?