The return of Kryptonians to their sector in space on the new Argo colony (as seen in the Ninth Season finale) has awoken the Green Lantern ring of Space Sector 2813, to seek out a new host. Unable to find anyone acceptable on the colony made up of Kryptonian clones, the ring continues its search until it reaches Earth and finds Superman.
Although Kal-El has no intention of leaving Earth to defend a space sector half way around the universe, he finds it impossible to turn down his new calling as even chucking the ring into deep space only eventually returns it to his finger.
Along with offering a cameo from John Stewart, who as the Earths’ current GL appears to have been tapped to showing Superman the ropes, and a brief history of Green Lanterns in the Smallville Universe, the opening issue to the latest Smallville mini-series also foreshadows looming problems with the Manhunters who are awoken as well on discovering a new Lantern has been chosen. Worth a look.