William Birkin is one of Umbrella Corporation's head scientist and the father of Sherry Birkin. His most notable discovery was The G-Virus, which is considered to be the most dangerous bioweapon in history.
Birkin almost died in an operation led by U.S.S. operative HUNK, where he subsequently injected himself with a G-Virus sample, eventually mutating into a creature known as "G" and killed most of his attackers, while accidentally spreading the t-Virus samples in the process, eventually leading to the infamous "Raccoon City incident."
