At the funeral of Green Lantern Abin Sur on the Green Lantern Corps' headquarters on Oa, the corrupted robotic predecessors of the Corps, the Manhunters, attack. You control Green Lantern Hal Jordan as he joins the fight to defend Oa against this menace, armed with the might of the power ring. However, there is far more to this assault with enemies where you least expect them as the GLC try to make sure that no evil will escape their sight.