Improve. Adapt. Overcome. The same lessons John Stewart learned in the Marine Corps help him begin his quest to find the other lost Lanterns in the dark sectors of space. Meanwhile, back on Oa, one of the Corps' newest members, Jo Mullein, alongside Young Justice's Teen Lantern and Simon Baz, tends to the wounded and investigates who or what caused the source of all Green Lanterns' power to go nuclear and wipe out the Corps.