Richard Stieg was a research assistant in the weapons systems research division of Massive Dynamic. At an unknown time, he was contacted by unknown persons and asked to steal research into airborne viral contagions - research that had been conducted by Walter Bishop and William Bell decades earlier. Setting up a laboratory in the U-Case Storage facility in Back Bay, Massachusetts, Stieg was able to manufacture a Flesh-melting contagion which causes the infected individual's skin to decompose in a matter of seconds. The contagion was then smuggled onto Flight 627 in his twin brother Morgan Steig's insulin pen. It is unknown whether or not Morgan knew he was carrying the contagion onto the plane.