The X-Files: Season 8, Episode 15

8 - 15: DeadAlive (2)

After Mulder was buried, Billy Miles who also was dead, somehow comes back to life. Skinner and Scully immediately dig up Mulder and found him to be alive too. Krycek offers Skinner a vaccine for Mulder's virus infection but he wants him to kill Scully's unborn child.