Mr. X, another man with no name,was Deep Throat's successor, and was a very different type of character. He was much more sinister, and when ever we saw him it was in a dark place and he was extremely worried about being seen. Several times he had refused to give any assistance to Mulder and Scully. In "One Breath" we saw what he is capable of, when he killed a man that was fleeing with a sample of Agent Scully's blood. He had been, on the whole, quite helpful with his information, until cancerman gave an order to kill him. But, we then saw that he was a friend, when dying, he wrote "SRSG", in his blood, to Mulder, which led Fox on the right track.
