Usually Superman is here to fight the alien menaces which come to plague us, standing as a champion of truth, justice and the American way.
But, in this classic Action Comics tale with cover by Curt Swan and George Klein, Superman joins them (the bad guys), as he turns into an "ant-man", and participates in....
The Invasion Of The Super-Ants!
As their ship was repaired, even the green Kryptonite was explained (it was their ship's fuel, not meant to harm Superman at all!).here!).