It's been six years since World War 3 happened. A nuclear war that destroyed all countries and wiped out the population. Except for groups of children that the government had sent into underground bunkers. Brexley Merandise is the leader of the last group, all girls. They haven't seen another group since they broke out of the bunker. But that changes one night when a boy comes across their territory. That's when she meets another group, of all boys. After meeting the flirtatious leader, Ren Amos, they decide to merge their groups together. But when a person from the past becomes an enemy, they're forced to put their bickering aside, as well as developing feelings. As dangers and threats keep coming, can Ren and Brexley keep their group safe?