Mulder is a fictional character from the television series The X-Files, created by Chris Carter. He is portrayed by actor David Duchovny and is known for his strong belief in the existence of extraterrestrial life and government conspiracies. As an FBI agent, Mulder investigates unsolved cases known as X-Files, which often involve paranormal phenomena. Throughout the series, Mulder is characterized by his relentless pursuit of the truth, often clashing with his skeptical partner, Dana Scully, played by Gillian Anderson. His personal experiences, including the mysterious disappearance of his sister, drive his obsession with uncovering hidden realities and challenging conventional beliefs.