The Night of the Bubbling Death - S3-E1
Revealing mistake: As West drags the body of a bad guy out of the scene, the supposedly unconscious man is holding his head up so as not to have his head dragged through the dirt. A truly unconscious person's head would flop back on to the ground.
Man's Best Friend Is Not His Dog - S4-E6
Revealing mistake: As Schultz holds Newkirk's hat during the search, you can see "Dawson" written on the inside band. This was to insure that Richard Dawson (Newkirk) always had the right wardrobe pieces.
Revealing mistake: On 10/9/06, John entered the storage facility and reached towards the light cord. He formed a fist, as if grasping the cord, but his hand was actually several inches from it. It was clear that he was not actually holding the cord at all, but then he pulled his fist down and the lights went on.
Meet My Master's Mother - S3-E9
Revealing mistake: The "ocean" behind Tony and his mother is a painted backdrop; the waves aren't moving. (00:20:10)
School Days - S1-E3
Revealing mistake: When Max is being attacked with throwing knives, one is thrown into the closet door. Watch closely; the wire used to guide the knife is visible.
There Were Giants in the Earth - S1-E5
Revealing mistake: The Robot's lights wink out for a few seconds as it disables the force field.
Revealing mistake: During his first confrontation with the alien, Hayata's pistol shoots powerful rays that don't cause a single speck of damage to the walls when the monster dodges them. They are just superimposed. (00:09:40)
Revealing mistake: Oliver and Eb cast shadows on the painted backdrop as Mr. Haney drives up.
It's All Done with Mirrors - S1-E27
Revealing mistake: During Scott and Kelly's scuffle in the restaurant, the stunt men's faces are visible several times. (00:27:25)