The exploits of FBI Special Agents Fox Mulder and Dana Scully who investigate X-Files: marginalized, unsolved cases involving paranormal phenomena. Mulder believes in the existence of aliens and the paranormal while Scully, a skeptic, is assigned to make scientific analyses of Mulder's discoveries that debunk Mulder's work and thus return him to mainstream cases.
While protecting a man due to testify against the Morley cigarette company, Skinner is horrified when the witness dies mysteriously. What the agents soon discover is that a new brand of cigarette has a dangerous secret.