When an alien alliance known as the Covenant lays siege to the planet Meridian, four high school students--Saskia, Dorian, Evie, and Victor--are thrust into battle to save their world. With their village in flames, the four find themselves stuck above ground, locked out of the town shelter where the rest of the survivors are gathers. With nothing but a few scavenged weapons and an injured Spartan, one of the UNSC's super-soldiers, they must tilt the battle for humanity's survival.