Rob and Frida's Battalion Zero has vanquished Dr. Dirt, but Dirt's accomplice, Lady Craven, has risen to power to finish what Dirt started: control of every biome boundary to rule the Overworld. The balance of day and night has shifted, and the mobs keep the villagers at bay, making them work ever harder during the day to replace what monsters destroy at night. Battalion Zero has suffered some losses and must regroup and recoup their resources and power.
Rob, Frida, Jools, and Stormie are now outcasts who must search the most desolate spaces for plunder as they attempt to gather new recruits who share their cause. Once a legitimate rancher, Rob reluctantly turns to rustling to provide horses to trade and to mount his company of defenders. The four friends become ever bolder and more desperate in their nightly raids against the mobs, and soon they bolster their ranks with outlaws De Vries and Crash, two shape-shifters who might get close enough to Lady Craven's inner circle to bring them down.
But artifice and deception can go too far. As Battalion Zero adopts the enemy's tactics, their very humanity hangs in the balance. Now the only soul that Captain Rob can trust is his honest steed, Saber. Can the two lead their cavalry cohorts back to the side of justice in time to retake the Overworld? Will Rob be able to resume his journey home? Or will they all remain in Overworld orbit forever, banished to the Far Lands to live or die? Saddle up for the next daring advance by Rob and company, Defenders of the Overworld!
