The Lonely - S1-E7
Other mistake: The supply crew arrives at the asteroid every 3 months, as established by the dialogue between Corry and the astronauts who bring him the female robot. However, Corry's narration reveals that he has been living with the robot for 11 months when the next supply ship arrives.
The Four of Us are Dying - S1-E13
Revealing mistake: As the men walk out of the alley, the block continues ahead of them. You can see it's a painted background.
The Four of Us are Dying - S1-E13
Visible crew/equipment: As Arch Hammer is walking to Hotel Real, the camera is looking up towards him as he walks. Just before he turns to go in, the lights, roof, and support beams of the soundstage are above the skyline backdrop.
Continuity mistake: Death has a bag full of purchases made from Lou. As they walk off, Death's bag disappears.
Continuity mistake: In the opening, Mr. Bookman has a toy replica of Robbie the Robot in his left hand in the close up, but a bottle in it a second later.
Other mistake: When Mike first walks into the town he sees the ringing church bell then looks to his right. The camera acting as his POV pans from left to right but since he was already looking to his right then the camera would be facing the direction he just came from.
Continuity mistake: In the vault, the book Mr. Bemis puts down flips open a moment before the atomic blast. After the explosion, the book is closed again.
Factual error: At the end of the episode, Major General George Harper looks out the window, puzzled. As he looks out the window, we see a palm tree in front of the building that is facing the window. Reims, France, is in northern France, where it is too cold to support that kind of tree. (00:23:00)
Continuity mistake: When Caswell walks toward the phone booth and the woman exits, she passes on his right side and walks down the sidewalk. Later in the scene Caswell gets trapped in the phone booth and breaks the window to get out. When he breaks the window, notice that the phone booth is no longer located on the sidewalk, it is now magically next to a building. (00:14:45 - 00:15:25)
Other mistake: Helen is holding the cup of rich "cocoa" that Markie supposedly just drank. Helen says, "I thought she'd finished her cocoa, and here it is untouched." Close-up on the "cocoa," which is clearly (so to speak) nothing more than water. (00:12:10)
Factual error: Captain Riker and Lt. Fitzgerald are wearing their insignia, which is incorrect. Officers serving in front line units did not wear their insignia because it identified them as high priority targets for Japanese snipers.
Continuity mistake: When the Ground Crewman runs after Lt. Decker, he reaches him just as Decker is climbing onto the plane. You see the Ground Crewman put his hand (or just about to) on Decker's upper left arm. When they cut to a closer shot, the Ground Crewman's hand is in the process of moving up to Decker's arm.
Continuity mistake: When Decker first gets out of his plane, Maj Wilson begins to question him. Decker's hair is neatly combed. When Wilson asks him "Are you French?" the shot changes to a closeup of Decker only. His hair is now disheveled in the front and hanging down on his forehead. The next shot returns to the wider angle and Decker's hair is more neatly combed again, as it originally was, not hanging on his forehead.
Revealing mistake: As Peter goes to the fishers, the pair shown on the bridge behind him are obviously photographs.
Revealing mistake: When "Selden" falls down the stairs it is obvious that it's a stunt double.
Continuity mistake: The jeep driver is standing behind Lt. Decker's aircraft during the initial conversation between Decker and Maj Wilson. His hands are behind the fuselage in the initial shot. When the shot changes to a close up of Decker, the driver's hands are now on top of the fuselage.
Character mistake: The "frozen" woman on the stairs during the welcome mayor scene repeatedly blinks her eyes.
Visible crew/equipment: Right after the phone conversation, everybody starts going towards the door. As they do, if you look at the couch on left you can very briefly see a shadow of something moving across it. It couldn't be any of the actors since they were all either outside or on the other side of couch.
I Shot an Arrow into the Air - S1-E15
Revealing mistake: Right after their friend dies and the commander talks about going into the mountains to search for any life signs, you can very briefly see Corry looking straight into the camera.
Answer: It's explained in the episode. The aliens are experimenting to see how humans react to various scenarios. This just happens to involve them using super strength.
Thanks. It's been a long time since I saw the episode so I forgot.