Stopover in a Quiet Town - S5-E30
Continuity mistake: Bob's cigarette sets the artificial grass on fire, and he rapidly stamps it out. When he finishes extinguishing the flames, the grass is scorched, but intact. He doesn't touch it again, but one shot later, the burned grass and all its ashes have vanished and a huge hole has appeared, revealing the metal mesh underneath. (00:13:50)
A Short Drink from a Certain Fountain - S5-E11
Continuity mistake: When Raymond arrives to check on Harmon, Flora is sitting at the breakfast bar opening the morning paper. She's holding it straight up in front of her, but when the shot reverses angles, the paper is suddenly lying flat on the bar. (00:16:15)
Living Doll - S5-E6
Continuity mistake: When Erich falls downstairs, Talky Tina flies off of the stairs too, yet in the next shot she's shown still rolling downstairs. (00:23:25)
Living Doll - S5-E6
Continuity mistake: When Erich throws Talky Tina across the room, when she hits the floor, her arms and hair change position between shots.
An Occurrence at Owl Creek Bridge - S5-E22
Continuity mistake: After crawling from the water onto the shore, the Southerner lies on his back with his shirt gaping open, exposing his entire chest. But in the next shot, his shirt has fastened itself, completely covering his chest again. (00:16:00)
Continuity mistake: After Oliver hits the bicyclist, the bike's front wheel is turned upright, but is still intact, and the boy has been thrown across a lawn to the edge of a phone booth. In the next shot, however, the wheel is suddenly crumpled, and the unconscious boy has somehow moved to a completely different place on the grass, several feet away from the phone booth. (00:01:00)
Continuity mistake: When Phyllis stumbles back toward the window, both its draperies are neatly in place. Next shot, just before she crashes through the glass, the drapes are suddenly half pulled down and a broken curtain rod that wasn't there seconds before hangs down over the window. (00:23:15)
Living Doll - S5-E6
Continuity mistake: When Christie walks up the path, from the car, with her mother, the package she holds swaps arms between shots.
Living Doll - S5-E6
Continuity mistake: After Erich takes Talky Tina back out of the trash can and pulls her from the burlap bag, the doll's left arm is pointing straight up above its head. When the shot cuts to a different angle, the arm is suddenly down at Tina's side, even though Erich didn't move it. (00:20:30)
Continuity mistake: Just before Sport and Jeb come back from their first visit with Aunt T, their parents are walking around the pool deck where it's fairly dry. But when the children come back, the area where they are helped out of the pool is suddenly very wet, probably from earlier takes. (00:13:40)
Continuity mistake: When Sport and Jab jump into the pool for last time, Sport is seen wearing a shirt. But,when she comes out at Aunt T's house she is wearing a swimsuit.
Continuity mistake: At the beginning, The main character is driving a car and hits a bicyclist and kills him. The inside shots from the car show the driver's window closed. The outside shots show the driver's window open.
Continuity mistake: After McNulty freezes the office, a co-worker is getting water from a faucet, and the water is frozen in motion, but right before McNulty unfreezes the office, a female co-worker is in the background at the faucet with no water coming out of the faucet.
The Brain Center at Whipple's - S5-E33
Continuity mistake: At the moment Chief Engineer Hanley turns off the projector, the lamps in the background come on at precisely the same moment. Mr. Whipple is standing in the middle of the room. No one else was in the room to turn the lights on.
Continuity mistake: When Joe goes to punch the TV screen, it shows moving lines and static. But in the shot where his fist goes through the screen, it's easy to see that the screen has been replaced with one on which wavy lines have simply been painted, and then backlit. The lines are still visible on the shards of glass after the screen is broken.
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.