Mark Young was an up and coming Massive Dynamic employee with the potential to be a star in the organization. However, he turned out to be selling technology from Massive Dynamic on the black market. Shortly after giving a presentation on the 33rd floor of the Massive Dynamic building, Young began hallucinating butterflies.
The butterflies "attacked" him and he began getting severe cuts all over his body. As a swarm of butterflies erupted from the radiator, he ran, and as he tried brushing them off, fell out of the window, plummeting to his death. Young was dosed with a potent psychoactive that caused his mind to believe he was being attacked, which in turn caused his body to create the wounds.
Nina Sharp posited that Young threw himself out of the window in response to stress caused to the "nature of his work", continuing on to explain that when one deals with the fringe of science, some realities may become too hard for one to handle.