SCP-049, otherwise known as The Plague Doctor, has a innate desire to purge the world of "the pestilence". He kills those who summon the will to oppose him, and uses their bodies for his experiments. But another entity, SCP-343, has taken an interest in The Plague Doctor. 343, or "God" as he is sometimes referred to as, takes SCP-049 on a journey through the past to see the beginning of the pestilence that has become the doctor's obsession. (imdb)