So, in the third episode of X-Men '97, we were introduced to Mister Sinister who is undoubtedly evil for causing Cyclops and Jean to be separated from Nathan Summers, their child. He nearly killed him with a techno-organic virus that could only be neutralized in the future. Bishop took Nathan to the future to save him from dying and causing the separation. So, a guy like this evil has to be the main villain of the show, but hey, I'm not making assumptions here, this was confirmed by Beau DeMayo, the writer of this series himself. So, in this article, get to know who Mister Sinister is in X-Men '97 before the story continues.

Mister Sinister wasn't always a psychotic mutant. His origin story dates back to the Victorian era when he was a famous and genius biologist named Nathaniel Essex. He developed excellent and advanced discoveries about human evolution. However, he was obsessed with Darwin's theory of evolution but according to him, Darwin and other great scientists could have done better research if they had thrown morality and medical ethics out the window.

While continuing his research on human evolution, he discovered that the human genome undergoes an increasing mutation he called the "Essex factor". But his theories were widely laughed at which made him bitter over time. He became so obsessed with his work that he ignored his family and was somewhat responsible for the death of his four-year-old son. This left him with a deep sense of remorse and he made it his life's mission to somehow revive his son.

He hired a group of thugs and named them the Marauders who abducted random people at night from the streets of London so he could perform experiments on them and even exhumed the body of his dead son for the sake of his experiments. He was quite successful with his experiments but his inhumane methods got him ostracized from society as well as his wife who called him "Sinister" on his last breath.