Little is known of the life of Charles Crillon prior to 1950.  He was known in that time as an amateur scientist and provacateur, publishing his observations in a pribate published work that was largely disdained by the larger scientific community.  He earned  the attention of the US military when a series of predictions he made about seismic events came eerily true in 1950.

The U.S. Military had developed a project to tap geothermal energy by creating a pipeline 50 miles beneath the surface on the outskirts of Civic City.  Crillon had long been a proponent of the concept that geologic events on the surface were not random or natural processes but the work of living beings deep in the Earth.  Because of the intense heat and pressure at such depths, Crillon speculated the only carbon based life forms that could survive would be composed of a diamond-like substances.  Crillon's theories, published in his own journal, were widely ridiculed.

But when Crillon reached out to the army predicting imminent geothermal disasters, the military hedged their bets by calling in the Justice Society,  Stationed at Old Reliable Geyser and Bottomless Lake, the JSA were witness to the sudden explosion of the geyser and the collapse and evacuation of the lake, rescuing those caught in the disasters.  Returning to the military base, they are briefed on Crillon's predictions.  Having heard of Crillon's "crackpot" theories, the JSA is dismissive but agrees to attend one of Crillon's expositions at his science club.

Arriving, the meet Crillon and the sole other guest, an odd looking man named Mr. Exnam.  As Crillon expounds on the existence of a race of diamond humanoids, the power goes out and when they JSA respond, Crillon and Exnam are gone.  Exnam is in fact one of the Diamond Men and takes Crillon deep into their lair.  Admiring his as the sole intelligence to identify them, they alter his form into diamond so he can join them after their conquest of Earth. They alter his body into diamond form and begin reprogramming his mind with propaganda to hate men of the surface world.

In the meantime, the JSA has found Crillon's notes and race to 3 new sites where the Diamond Men emerge and create mayhem.  The JSA's attacks are repelled by the Diamond Men's weapons, that blind them and send them seemingly to their deaths.  In reality, all survive and meet back as the military base where Crillon, who has rejected the Diamond Men's conditioning and escaped, arrives with news of their plans.  As the Flash turns up the radio for news, the vibrations cause Crillon severe pain and the JSA now realize they have a weapon against their foes.

As a diamond fortress emerges from the Earth, the JSA use all manner of loud souning implements to shatter the Diamondoids and their equipment.  Crillon is restored to normal through unusual radiation treatments and is finally recognized for his scientific accumen (All-Star Comics #51).

The later activities of Charles Crillon are not recorded.  Whether he retained any of his diamond forms abilities or the mental conditioning of the Diamond Men is unknown