- Edmond Hamilton
- Curt Swan
- George Klein
- Superman; Supergirl (guest star); Rog-Ar (intro, villain, flashback); Jor-El (flashback); Perry White; Phantom Zone inhabitants [Quex-Ul (intro); Jax-Ur; Professor Vakox; Dr. Xadu; Mon-El]
- Superman releases Quex-Ul from the Phantom Zone since he has served his sentence, but Quex-Ul vows revenge on the son of the man who pronounced him guilty. However, when Quex-Ul displays heroic behavior, Superman wonders if he was truly guilty and travels back in time to Krypton to witness Quex-Ul being hypnotized into believing himself guilty. When Supergirl tells Quex-Ul he is innocent, he sacrifices himself to keep Superman from being exposed to a Gold Kryptonite trap he has set for him. In doing so, Quex-Ul loses his powers and memory, so Superman sets him up in a new life in Metropolis.
- Fortress of Solitude; gold kryptonite (intro in non-imaginary story); Krypton (flashback); Phantom Zone
Quex-Ul's next appearance is in The Phantom Zone #1.
Gold Kryptonite's first appearance, in an imaginary story, was in Adventure Comics #299.
This story establishes that 18 Kryptonian sun-cycles is about 25 Earth years.