Dimitri Durovich was originally a mild-mannered nuclear physicist assigned to the operation of the Chernobyl nuclear power plant. As luck would have it, he was at work the day the reactor coolant failed, specifically due to the incompetence of his staff.
Knowing that the thermal reaction was going to be catastrophic, Dimitri stayed behind to try and repair the coolant system while his underlings contacted the authorities to warn the nearby town of Pripyat of the imminent disaster. They fled while Dimitri sacrificed himself.
Of course, while countless others died in the immediate aftermath of the reactor’s meltdown, Dimitri did not. He was instead… changed. The intense radiation surrounding and suffusing his body did not tear his cellular structure apart, but changed it.
Suddenly absorbing vast amounts of the nuclear radiation around him, Dimitri hit his upper limits… and then began to shed the harmful energies. It was at this point that he met the American, Jenny Swensen, who had journeyed there in her experimental, Mark 1 M.A.X. armor!
She helped Dimitri to cool off, since he was also giving off deadly amounts of heat, by opening a tunnel into an underground river stream. Once he was cooled off, Dimitri told Jenny to bury him in stone, in order to stop his body from contaminating the surrounding area any more.
Though she didn’t want to, Jenny did indeed honor Dimitri’s wish, and flew off once she’d entombed the man in the rock that surrounded them. Whether or not this was the end of Dimitri remains to be seen however; he did survive being at ground zero of the Chernobyl incident, after all.
If his newfound powers could protect him from there, perhaps being buried alive isn’t enough to end his life either. As radioactive as the area around him is despite his efforts, it’s quite possible that Dimitri’s absorption power has been keeping him going to this very day…!