Green Lantern #68

Green Lantern #68 (On Sale: February 27, 1969) has a cover by Gil Kane.

"I Wonder Where the Yellow Went" is by Denny O'Neil, Gil Kane and Joe Giella. Green Lantern pursues a gang of space outlaws into a field of meteors. One of the meteors is made of sulfur. When it explodes Green Lantern is caught in a cloud of yellow gas which allows one of the outlaws to make it to Earth.

Unable to find the outlaw, Green Lantern returns to Evergreen City and is approached by Professor Cally. The man claims to have discovered a filter which will remove the power ring's yellow vulnerability. Green Lantern agrees to test the filter over the next week with promising results.

A week later, while Green Lantern is battling a group of gangsters his ring begins to weaken. Professor Cally then reveals himself to be the space outlaw Commander Calibax, who has discovered that the filter will destroy a power ring over time. Without his ring, Green Lantern is nearly killed. Calibax then threatens Eve Doremus and her father, but Green Lantern is able to beat him using only his wits and fists. After Calibax is safely in custody, the Guardians provide Hal with a new power ring.

Edited by Julius Schwartz.