I came here to give you some valuable advice." This is how the man known only as Deep Throat introduces himself in the second episode of the series, setting up a relationship with Fox Mulder that defined the tone and direction of The X-Files. Elusive, mysterious and sometimes duplicitous, Deep Throat dangled tidbits of information before Mulder and Scully to entice them into cases that they might otherwise overlook, to draw them along lines of inquiry that might be disregarded, and sometimes to divert their attention from areas he wanted them out of. He rarely answered a question directly, and when he did, it was always on his own terms. He obviously knew as much about Mulder's work as Mulder did, and admitted to watching him for a long time from "his lofty position." Whether it was with the intent of helping the younger man uncover the truth (as he often said) or to hinder him through misdirection, he was always an important source of information. Manipulative, avuncular and enigmatic, he created a presence in The X-Files before sacrificing himself for his protege in the final episode of the first season, "The Erlenmeyer Flask."