If the zombie apocalypse happens tomorrow—how would you spend your last day? 

All Dr. Brianna Lewis wants is a cup of coffee. 

Coffee, to make slaving away in her cell culture lab at Green Fields Biotech a little more bearable on a Friday afternoon when everyone is home already. 

What she doesn't count on is a group of terrorists blowing up all the entrances to the building and taking her and a select few others hostage. Bree soon finds herself conflicted. Not only does she know their charismatic leader. She also starts to suspect that there is a lot more to this than the hunt for an illegal bioweapon—a virus that could potentially kill millions in just a few days—particularly as there is currently a flu epidemic raging across the country, and reports about violent behavior among the afflicted are getting more and more alarming.