Other mistake: In order to leave such bloody footprints, CSM must have stepped into the puddle of blood. It is impossible because the guy shot by CSM could not bleed so much blood in such short time, not mentioning that CSM must have intentionally stepped into it. (00:05:20)
Continuity mistake: The chessboard was knocked down by the falling Russian, however in the next shot it is still on the table. (00:02:55)
Continuity mistake: When Dara walks toward the angel, there is only one car, parked on the right side of the street, but when her father approaches her, there is another car parked on the opposite side of the street. (00:02:50)
Unrequited - S4-E16
Continuity mistake: When Scully and Mulder run away from the dogs, the gate is fully open, while in the previous and next shot only the door is open. Plus their car standing in front of the gate is missing. (00:09:30)
Continuity mistake: The wedding ring Ariel is holding in her outstretched hand is either vertically protruding from the palm of her hand or is hidden inside of it, depending on the shot. (00:40:25)
Continuity mistake: While Mulder's waiting for Langly and Frohike to unlock the exit door, Gray-Haired Man keeps shooting at the glass door, and the increasing bullet damage on the glass doesn't stay consistent as more damage occurs, and changes between the closeups and wideshots.
Continuity mistake: When Mulder and Byers find Scully in Penny's room, there is a black stripe on the ceiling of the corridor, while in the scene when Scully is leaving the room there is no stripe there. (00:36:50)
Never Again - S4-E13
Continuity mistake: In the front shot Scully holds the photo with 2 fingers (thumb and index), while in the back shot she uses three fingers (thumb, index, and middle). (00:24:55)
Continuity mistake: When Mulder is talking to Dana's mom about finding her cross (necklace) in the trunk, Scully's mom says that she gave it to her on her 15th birthday, but in Season 5 in Christmas Carol, Scully has a flashback to receiving it at Christmas. (00:41:40 - 00:43:55)
Mind's Eye - S5-E16
Continuity mistake: While talking through the jail glass, Marty's face is generally directed straight toward Mulder's face when reflected in the glass, but her head is twisted to the right when filmed from Mulder's side. (00:34:40)
Mind's Eye - S5-E16
Visible crew/equipment: During the scene of Marty's interrogation there is some dark blue element behind Mulder when he is reflected in the mirror. However, in the frontal scene there is just a plain wall behind him. (00:24:00)
Mind's Eye - S5-E16
Continuity mistake: When the policeman passes the phone over to Marty, in the first shot from behind she holds it with two hands, while in the next frontal shot she grabs it with her left hand and then with the right hand. (00:13:20)
Mind's Eye - S5-E16
Other mistake: Since the apartment was supposedly "turned inside out and upside down, " as Detective Pennock claims, it would be practically impossible that such an obvious place as the shaving blades container not be dug up thoroughly by the police. (00:12:15)
Character mistake: While examining Agent Michel's body, the doctor says to Arthur Dales about "toxology report" instead of "toxicology report." Toxology is the study of archery. (00:26:50)
Nothing Important Happened Today (1) - S9-E1
Continuity mistake: During the previous episode, Skinner receives a nasty gash on his head courtesy of Billy Miles. This episode takes place 48 hours later and there is no indication whatsoever that Skinner received such an injury (the wound is visible once again in the next episode). (00:15:35)
The Red and the Black (2) - S5-E14
Continuity mistake: While in the car with Scully, Mulder turns his head aside of Scully towards the side window twice: once when the shot is facing Scully, and just after in the shot facing him. (00:40:25)
The Red and the Black (2) - S5-E14
Revealing mistake: It seems that in the first shot the doctor injects something into the vaccine vial rather than extracting from it since the syringe plunger is moving inwards instead of outwards. In the next shot one can see that the syringe is being filled with the vaccine, however the arrangement of doctor's fingers is suitable for injection, which strongly suggests that the scene is played backwards. (00:17:55)
Continuity mistake: Uroff-Koltoff Star of Russia in New York Harbor is a completely different ship from Uroff-Koltoff Star of Russia leaving Vladivostok at 17:45. (00:33:10)
Invocation - S8-E5
Continuity mistake: In this episode the character of Billy Underwood was played by twin brothers Kyle and Ryan Pepi. If you pay attention you can tell when one twin was being used instead of the other as one of them has two freckles on his neck and another two by his right eye whereas the other does not.
Roadrunners - S8-E4
Factual error: The End of the episode shows Scully recuperating at the BYU Medical Center in Provo, Utah. However, on the flagpole outside of the center you can see the Kansas state flag. (00:42:20)
Answer: As he stated many times throughout the series, Mulder needed Scully to be sober and skeptical. Whenever Scully's skepticism wavered and she started questioning her own rationality, Mulder would try to restore her sense of skepticism, because he needed her to be clear-thinking.
Charles Austin Miller