Giant Superman Album #40

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.