Karis Hylen has been through the New York City dating wringer. After years of failed relationships, she abandons her social life and whittles her days down to work and spending time with her dog, Zeke. Her self-imposed exile ends up saving her life when an untreatable virus sweeps the east coast, killing millions.

Alone in her apartment building, Karis survives with only Zeke, phone calls to her mom, and conversations with two young girls living across the courtyard. With the city in a state of martial law, violence and the smell of rotting corpses surround her every day. But her biggest enemy is her own mind. As cabin fever sets in, vivid hallucinations make her question her sanity.

In addition to her dwindling food and water stash, Karis must now struggle to keep her mind in check. When a mysterious man enters the scene, she hopes she can convince him to help her make it to the quarantine border. With the world crumbling around her, Karis discovers her inner strength but may find that she needs people after all.