"You cannot harm one who has dreamed a dream like I have."
- – Jason Ironheart
Ironheart was an instructor at the Psi Corps Academy, specializing in, amongst other things, fringe skills. While working as an instructor, he helped to teach and train Talia Winters and the two had, by Winters' account, a brief but passionate affair. The two would remain in touch over the succeeding years, albeit sporadically. Without knowing the exact nature of the project or its goals, he volunteered for a secret project and underwent a variety of treatments. These included genetic manipulation and injections of acetylcholine and mutated serotonin by the Corps to enhance his telepathic ability and to attempt to create a stable telekinetic. The experiment caused his powers to grow to an unmanageable and unstable level. He also was able to pierce any telepathic block, allowing him to learn the truth about the Psi Corps: power and control was what they sought above all else.
He and another escaped to Babylon 5 but were followed by Psi Cops Alfred Bester and Kelsey. Jeffrey Sinclair was approached by the Psi Cops to help them apprehend Ironheart. However, Ironheart waited until Winters was subjected to a painful joint deep scan by the Psi Cops before approaching her. She expressed some resentment at this, and she and Ironheart retired to Winters' quarters to talk in private. Once he told her what he had found out or otherwise surmised about the Psi Corps' goals, she was visibly shaken. Both persuaded Sinclair that Ironheart's powers were too dangerous to be claimed by the Psi Corps, who wished to create telekinetic assassins. Sinclair agreed to help him escape ordering a fake safety drill to evacuate the route to Ironheart's escape.
Escorted by Winters and Sinclair, Ironheart hurried to his ship but was stopped by Bester and Kelsey, who was vaporized when she drew a PPG against him. In the turmoil and mindquake he managed to exit the station onboard his ship. As his ship hovered nearby, suddenly an energy field enveloped it.His powers grew to such a level that he ascended into a being of pure energy. Before departing, he thanked Sinclair, telling him that he would see him in a million years, when humanity will have evolved into Vorlon-like energy beings. 
As a final gift to his former lover, Ironheart gave Winters rudimentary telekinetic powers.