Superboy’s second run in Adventure Comics comes to a close in issue 458, with the xenophobe story by David Michelinie, Joe Staton and Jack Abel.
Thanks to his mental control of Ma and Pa Kent, Lester Wallac learns of the Phantom Zone projector, and uses it against Superboy, sending him to the Zone. There Superboy encounters Zan-Em, who has been mentally influencing Wallace and controlling his actions!
Seeing Wallace about to attack Lana Lang with a knife, Superboy defeats Zan-Em and re-emerges from the Zone. With Zan-Em defeated, Wallace regains control of his mind, realizes what he has done, and uses the Phantom Zone projector on himself.
Superboy’s series moves briefly back into Superman Family.
The conclusion of the Eclipso story by Len Wein and Joe Orlando reveals that, permanently split, Eclipso and Bruce Gordon will each fade from existence. Eclipso has rigged a Zeiss projector to draw stellar power that will enable him to survive while Bruce perishes.
But of course Bruce tracks him down, and the combination of the black diamond, and Professor Bennet’s re-rigging of the Zeiss projector re-merge Eclipso and Bruce Gordon.
An adequate Eclipso story, but nothing memorable.
Both Eclipso and Bruce Gordon next appear in the pages of Green Lantern through the early 80s. Professor Bennet and Mona have to wait until Eclipso’s next solo outing for their returns, in the Eclipso: The Darkness Within mini-series and follow-up book in the mid-90s.