Sebastian (Babylon 5)
In the late 19th century, a man named Sebastian (who lived at 14B Heresford Lane in London on Earth), disgusted at the immorality of the world, began to believe that he was on a holy crusade. It was his mission, he thought, to stop London from sinking into immorality and decay. He became a serial killer and murdered many prostitutes on the East End of London, becoming known as Jack the Ripper.
On Friday, November 11, 1888, he was abducted by the Vorlons, and shown the terrible depth of his mistakes. They decided to make use of him as an Inquisitor, and kept him in stasis when he wasn't needed.
He was called to test Delenn by Kosh Naranek, to make sure she was one of the chosen to stand against the Shadows. Sebastian bombarded her with the question of "who are you" with the goal of breaking her and having her prove her inferiority. When Captain John Sheridan heard of the torture that Sebastian was putting Delenn through, he attempted to stop it only to become part of the test. When Sheridan and Delenn proved that they would die for each other without anyone knowing, he determined that they were the chosen ones (since they were not fighting for their own glory).
Sheridan later did some checking on Sebastian's background that was given to him, and determined that Sebastian was Jack the Ripper. He confronted him with this information. Sebastian merely wished Sheridan good luck with his own holy cause, and hoped that his decisions would have better results than his own. Having finally found the chosen ones, he hoped the Vorlons would finally let him die.