When a zombie pandemic sweeps the land, a group of survivors hide out in an Upper East Side apartment building. As food supplies dwindle tensions rise, and their only salvation appears in the form of Mona, a mysterious girl who repels the zombies. Though Mona brings food to the survivors and a new sense of possibility, they wonder why she's impervious to the zombie hordes and endeavour to discover her secret. But their decision to put it to the test could shatter the safe, careful world they've built for themselves.