A young woman enters an underground storage facility, where she soon finds herself trapped and stalked by a killer.

When Ella discovers her Wall Street banker boyfriend is renting a secret storage unit, she suspects he's using it to hide an affair. Enlisting the help of her best friend Molly she breaks into the facility only to discover something more terrifying instead. Now trapped in a darkened building with a group of neurotic strangers who start disappearing one by one, Ella soon uncovers even worse horror in the dank depths. Her life or death battle to escape eternal enslavement is about to begin....

Ella is a former call girl who is now engaged. Her fiance is a minimalist who often puts their belongings in storage. One day Ella realizes he has been through her nightstand and her little black book is missing. Not wanting to risk his looking at it, she enlists the help of her best friend Molly to retrieve it from the storage under the guise that she thinks he's cheating. At the storage facility, Ella and Molly inadvertently attract the attention of a mysterious creature and a psychopath.