Episode #4.3 - S4-E3
Deliberate mistake: Before the gas explodes in the sewer, you can see the base of the Davy lamp glow red. Except that in real life this doesn't happen; the flame simply turns blue and grows taller in the presence of gas. This was probably done to make the scene more dramatic, though.
Deliberate mistake: In the scenes that take place in Kentucky, none of the characters speak with a Kentucky dialect.
Deliberate mistake: Elliot threatens Olivia about her testing positive for Oxycontin because she drank a peppermint mocha he brought her. If she tests positive she loses custody of her child. The thing with Oxy is that it's in one's system for a maximum of 4 days. Could be even less if only a small amount was taken and somebody exercises and drinks lots of water. Somebody could also eat poppyseeds and that would give a false positive. She could say she ate a poppyseed bagel. (00:14:00 - 00:16:00)
Deliberate mistake: Because the series changed networks after the end of season one, this episode completely ignores that season's cliffhanger about Harm being arrested as a suspect in the murder of Lt. Schonke.
Deliberate mistake: *SPOILER ALERT* Behind T-Bag is the actor who plays Lechero, and Lechero had just died in the episode. The person was not Lechero, but maybe they didn't have another extra at hand to replace him. 'Time 1' and 'Time 2' are taken from Netflix at the time this was posted. (00:29:46 - 00:30:25)
Deliberate mistake: Around the 26 minute mark, when Charles Brandon joins Margaret for a game of cards during their voyage to Portugal, Margaret has a glass of wine (and later Brandon) in which the liquid is not sloshing around As It Should Be on a ship that is rocking and swaying the way it should. (00:26:10)
Deliberate mistake: At the end, a line apparently cut earlier creates slight confusion. Nick says to Nat, "When LaCroix asked you why?" (why save vampires). In the earlier scene as shown, the elusive LaCroix spoke only briefly to Nat in the lab, and never asked her that question. (00:42:20)
Log 1: The Impossible Mission - S1-E1
Deliberate mistake: Halfway through the episode, they are chasing car thieves in a drainage channel. The thief's car comes to the end of the road and crashes into a deeper gully. You can see that the windshield has been taken out of the car, although it was previously there. They cut away and when they come back, parts of the windshield are back in the car, but the whole center is missing.
Deliberate mistake: The day of his scheduled departure, Poirot overhears conversations (mainly the one from the window of his room) he couldn't possibly be hearing given the long distance outdoors and the tone of voice. His reactions are shown as if he could hear and not simply see and infer the meaning. (00:23:00)
Crucifixed - S5-E10
Deliberate mistake: When Tara is talking to Gemma in the parking lot of Stockton Prison, the chrome bumper of Tara's SUV is blurred out, probably to cover up visible crew and equipment. It looks unnatural, since the image is sharp enough that you can see the radiator itself behind the grille, and the numberplate is perfectly sharp.
Deliberate mistake: Because the opening narration was adapted from the original American series, the phrase describing the role of the Crown Prosecutors (e.g. "prosecutors who prosecute") is redundant.
Deliberate mistake: Unavoidable, but still noteworthy: At the beginning of season 2, all the story lines pick up where they left of from at the end of season one; indicating that not much time has elapsed. In spite of this, most of the cast have different haircuts, Dana has grown out her fringe, and Tina suddenly has a baby bump.
Deliberate mistake: In the episode January 2011 where Stephanie puts a slide in the living room, when Stephanie goes down it, you can see she is using a stunt double because her hair is thicker and they cover her face with her arm.
Deliberate mistake: We see the Air Force plane's bomb bay doors come open. But in the next shot of the plane banking, the doors are instantly closed again. (00:45:20)
Deliberate mistake: David is shown to have an illegal weapon in his home even though gun control is quite strict in the U.K. Sadly, this is quite a common practice by returning war veterans who feel safer with a gun in the house, as they often suffer from PTSD, as David does.
Deliberate mistake: When filming the fake movie with Sophie playing the nun, many holes are made in the door, but when she slowly kneels to the ground, there isn't a hole behind her, so it seems like she's been miraculously saved. But as the scene continues, the nun starts to bleed and dies. Technically, they couldn't safely put a squib that close to her. (00:21:15)
Plane Death - S1-E14
Deliberate mistake: When the bad guy goes to smash a table onto Michael Landon notice the plate of glass in front of him, visible. The glass is there so Landon doesn't get hurt and to make the table break into pieces in front of him.
Winterfest - S10-E9
Deliberate mistake: Even though it's supposed to be Christmas time, the trees are lush with green leaves, no breath is visible when the actors talk and in the background you can see people wearing shorts and T-shirts.
The Night of the Pelican - S4-E13
Deliberate mistake: After Jeremy Pike drops the box in front of the firing squad and it begins to emit smoke, the wind blows the smoke to the right. The actors playing the soldiers in the firing squad then move themselves into the smoke and begin coughing and choking from it.
Mercy Moment Murder Measure - S1-E7
Deliberate mistake: When Abraham throws the secret note into the fire, he crumples it up before tossing it in. But then we see a shot of the note lying open and flat on the log before burning. Not only would the note not be able to uncrumple itself, it shows no sign of being crumpled in the first place. This was obviously done deliberately so the audience could read the note one last time.