High Quality Content by WIKIPEDIA articles! The Smoking Man (sometimes referred to as Cancer Man, the Cigarette-Smoking Man, CSM or C-Man) is a fictional character and the antagonist on the American science fiction television series The X-Files. He serves as the arch-nemesis of FBI Special Agent Fox Mulder. Although his name is revealed to purportedly be C.G.B. Spender in the show`s sixth season, fans continue to refer to him as the Smoking Man because he is almost always seen chain-smoking Morley cigarettes and because he, like other series villains, has multiple aliases.