"The Plot to Conquer the Universe"
Green Lantern finds himself a hypnotic pawn of spies to whom he mails secrets, so he gets the idea of turning himself into a letter and mailing himself to them.
"The Spies Who Owned Green Lantern"
Evil Star, a new foe of Green Lantern, battles and captures the Emerald Gladiator and impersonates him as part of a plot to destroy the Guardians and Green Lantern Corps.