Factual error: A scene in a photographic darkroom shows Michael Gambon developing a colour print in a dish under safe lights. Not possible. Colour printing must be carried out in pitch dark usually inside a light tight print processor, as colour photographic paper is sensitive to all wavelengths of visible light.
Character mistake: A shot shows Djimon Hounsou completing his year entry on a large chalk board. The entries are 20 years apart. The third entry on the second line is 2274, the next should be 2294, but instead it records 2394. The one after corrects the sequence with 2314. Considering there is an entry only every twenty years, you would think he'd be more careful. (00:20:15)
Us vs. Them - S2-E2
Factual error: We see Liam's driver's license. It says he's from Rhode Island, but the license looks nothing like RI's. It's issued by the State Motor Vehicle Commission, but RI does not have an MVC (only New Jersey does). And the expiration date is always the same as the holder's birthday, but here we see it's 2 days after his birthday.
Plot hole: When Nicky goes into prison in Mexico to give a criminal a shot of insulin, two errors are seen. 1) The needle and syringe are far too big for an insulin shot, which takes a one ml syringe and a small sub-cutaneous needle. 2) When we first see the syringe, there is a small amount of insulin in it, but it grows the more times we see it, until a large syringe is two-thirds full - insulin is enough in a one ml syringe.
Revealing mistake: Mr Knight shoots Suzie Boreton - after the muzzle flashes and sounds stop the bolt of his MK14 EBR continues to move back and forth as if it's still firing. (00:30:30)
Continuity mistake: When Buzz and Provenza race out of the squad room to follow Rusty in the frantic search for Stroh, Buzz is in shirt sleeves with no tie. However when they arrive at their destination Buzz is wearing a coat and tie.
Visible crew/equipment: As Joe approaches the third car with the bad guy in it, there is an unknown man, possibly a crew member, reflected in the back window where there wasn't a man before.
Episode #3.1 - S3-E1
Continuity mistake: DI Chandler calls a suspect "Daniel Wilkie." However when the interview is done he goes and talks to Ed, saying "you've just arrested Ben Wilkie."
Revealing mistake: When the thief places The Blue Carbuncle in the goose's throat, it's obvious he actually doesn't put the gem in the bird's mouth. He pretends to, but then drops the gem into his other hand. This is all visible in the shot.
Continuity mistake: Early in the episode as she is on a fire escape looking to hide somewhere, the window she opens from the outside has two half panes of glass, but on the inside it only has one pane of glass.
Factual error: Chief Superintendent Hilton wears the ribbons of the General Service Medal (awarded for military service in a combat zone, most commonly in Northern Ireland) and the Police Long Service and Good Conduct Medal (awarded for twenty years' service), but not the Golden Jubilee Medal (awarded to all officers with five years' service in 2002), which he would also have. When he reappears in Series 4, he is wearing the Golden Jubilee Medal, Diamond Jubilee Medal (awarded in 2012) and Police Long Service and Good Conduct Medal, which would all be correct, but no longer has the General Service Medal.
A Single Piece Was Lost - S1-E10
Visible crew/equipment: When the Gruenaks attack the Scientist a puppeteer is visible to the right of one of the Gruenaks, just before it grabs the bird cage and throws it onto the Scientist's head. (00:28:18)
Character mistake: The FBI team responds to a murder crime scene. The victim is lying face down in the bed with blood everywhere. The team leader takes the victim's wrist with his bare ungloved hand. A trained FBI agent would never touch a murder victim without gloves - one to protect himself and two not to contaminate the crime scene. (00:10:00)
Is Lupin Burning... ?! - S1-E1
Other mistake: The logo of the evil organization, Scorpion, contains just a little misspelling. It's missing the R. (00:02:50)
Continuity mistake: Kurt is still recovering from the beating he took in the previous episode with bad cuts on his forehead, checks and temple area. They are red and impossible to miss while he is in the police station. The cuts have miraculously disappeared in the next scene when he goes to visit Mona.
Factual error: The show, which is set in California in 1947, mentions the gas chamber, lethal injection and the electric chair as methods of execution in the state. Two murderers are sentenced to death by lethal injection and one is depicted being instead executed in the electric chair, which the governor states has been brought out of retirement for the occasion. In fact, California adopted the gas chamber as its sole method of execution in 1937 (having previously used hanging). Lethal injection was not used in the United States at all until 1982 and not adopted in California until 1993 (becoming the prime method in 1996). California has never used the electric chair.
Here There Be Dragons - S2-E11
Visible crew/equipment: When Prax leads the group to where Dr. Strickland took Mei, just as they reach the door the two green and yellow T-marks are visible on the floor. (00:02:30)
Episode #1.4 - S1-E4
Revealing mistake: The tabloid story with the plight of the Latimers just came out, and various characters are looking at it. In the bit when David Tennant tosses on the desk his copy of the Herald, the second paragraph of the second column goes "Sitting in the family home, surrounded by pictures and mementos of Danny" etc. It is the same text that was at the very beginning of the article when the store owner was looking at it. The newspaper is a prop with the same text in a loop. (00:35:00 - 00:36:30)
Who Burned Mr. Brinker's Store?: Part 1 - S1-E6
Other mistake: The arson investigators name Jamal as the main suspect in setting fire to the store, because the security camera caught him sliding something through the front door mail-slot. Any arson expert would immediately know that it wasn't Jamal that started the fire, as the fire's point of origin was in the back of store, and was also entirely contained there, and Jamal was not only nowhere near the back of the store, but was also outside.
Other mistake: Danny Stevens, an undercover police officer, is killed. The police agree to investigate the murder of his undercover persona, Steve Daniels, thus allowing the investigation of his death without compromising their ongoing investigation into the activities of a drug kingpin. The officer investigating the murder visits the kingpin to ask about Steve's murder. She shows him a photo of the murdered man, but the name across the bottom is Danny Stevens - the policeman's real name.