After fleeing for safety when a deadly virus pandemic upends their world, Sara and Dane take refuge in a hidden bunker. Her family should have reached the site within the first seventy-two hours...but they haven't. Convinced they are at the Plan B location, Sara will risk everything to find her family before it's too late.

With the world outside in chaos, Dane believes leaving the bunker is a bad idea—the virus isn't the only thing to fear. But Sara's determined to find her family, so he'll do whatever it takes to protect the woman who saved his life and stole his heart. Forced to fight for their lives, he hopes they survive long enough to make a future together in a new and unpredictable world.