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.
Scully faces her Catholic faith and the loss of her daughter Emily when she is asked to help a family whose adopted daughter was found dead in a position that looked like she was struck down by God himself.