- Sorry, Blackhawk -- but those secrets were dreamed up when I was the Moonster! As a plain old scientist, I can't duplicate them!
- — Gerald Monroe src
In the 1960s, Gerald Monroe suffered a laboratory accident which erased his old personality, created a new one, and developed an amazing array of new scientific devices and inventions. He called himself the "Moonster" and undertook a defense of the Moon, against all scientific exploration. His fiance Naomi aided the Blackhawks in stopping his insane rampage. Monroe's former personality was restored, by unknown means, and his advanced knowledge of science was lost.
The "Moonster's" Moon-shaped spaceship was sunk in the ocean. Blackhawk and his team know where it sank.
- Moonster's spaceship is a hollow miniature copy of Earth's Moon, maneuverable in orbit or atmosphere, capable of creating local solar eclipses over particular targets, and equipped with:
- giant robot armature
- radar / photography jammer
- protective anti-missile bubble
- Shipboard Moon Madness Rays (aka "Moonglow")
- Shipboard Tidal Wave Ray
- Moonster's personal "instant freeze" weapon
- This version of Gerald Monroe (Earth-One), including all history and corresponding appearances, was erased from existence following the collapse of the original Multiverse in the 1985–86 Crisis on Infinite Earths limited series. Even though versions of the character may have since appeared, this information does not apply to those versions.
- 1 Appearances of Gerald Monroe (Earth-One)
- 1 Images featuring Gerald Monroe (Earth-One)
- 2 Quotations by or about Gerald Monroe (Earth-One)
- Character Gallery: Gerald Monroe (Earth-One)