Nothing is known of the life of Henry Ross before 1941, when he was a biologist  appoint at the State Radiological Institute in Gotham City.  There he conducted research attempting to determine if radiation could restore vital forces postmortem.  Early work using dogs euthanized at the local pound were successful, and the dogs were revitalized, though after protracted exposure during which Ross dozed off and was awakened by his junior faculty, Johnston, to a room full of live dogs.  Excited, Ross ran to the Institute to share his findings, only to be rebuffed by his skeptical superiors.  They accused Ross of using radium for his own, dubious purposes rather than scientific research and requested his resignation.  Furious and knowing he needed to revive a dead human to be believed, he went home and committed suicide, leaving instructions for Johnston to revive him with his radium-based serum when he arrived.

Johnston followed his instructions and was astonished when Ross was indeed revived.  When initial results showed that he cleared the more toxic radium components, Ross stepped outside to savor his success.  He was confused when he touched a rose and it withered in his hand and then when a sparrow landed to his palm to feed but immediately dropped dead.  He returned to his lab to find an agitated Johnston and the news that the initial reads were incomplete, radium was indeed in his body and spreading.   When the rushed to his lab to get x-rays, they found them unnecessary - Ross was glowing in the dark.  In their furor, Ross accidentally touches Johnston, killing him instantly.  The police, unaware of Ross' condition, rule the death an accident but Ross realizes he must find an antidote.

Initial studies suggested an expensive drug for radiation poisoning called Volitell would neutralize the radium in his system.  Unfortunately a fairly high dose only lasted 24 hours, requiring constant dosing.  Lacking funds, Ross resort to crime, robbing local hospitals of their supplies, wearing a special suit to contain his radiation.  His activities eventually attracted the attention of Batman and Robin, who confronted him during one of his robberies,  To escape, he removed on his gloves to decay a pipe that he and the Dynamic Duo were climbing down.  In so doing, the pipe gave way, letting Ross escape but costing him a glove.  Using forensic techniques, Batman recovered fingerprints and since the Radiological Institute is a civil service job, Ross' fingerprints are on file.

Now dubbed Professor Radium by the press, Ross finds the volitell is becoming less and less effective and the radiation is becoming more potent, distorting him physically and mentally.  When Batman and Robin ambush him in his home, he attempts to kill them and failing  that flees, ultimately ending up on Gotham Shipyard.  There adopt a crane, Professor Radium tries repeatedly to kill the dynamic duo until he loses his balance and falls into the dark waters below.  When he does not re-surface, he is presumed deceased, tho Batman regrets that at the beginning of his path, Ross was trying to accomplish great good (Batman #8).

Whether Professor Radium is truly dead or whether he somehow survived is unknown