Interstellar Islands

The world finally had its third and then final war. Two remaining teenagers, Marlow and Zane are left surviving in a church bunker with nothing but a couple ducks. They've watched everyone they love, pass on from the toxic conditions and know they aren't far behind them. When they are found by a team scavenging for supplies, the teenagers don't believe the claims that they are from the asteroid belt, the last settlement of humans that made it off Earth just before it all went to hell. They don't believe they live out there on Interstellar Islands with artificial atmospheres. They don't believe but they don't have much choice but to board their ship and see where it takes them. Whatever the people from the belt have in store for them can't be worse than what's left on Earth. Can it?