Plot hole: The FBI is looking for a "very tall" guy who has been identified as such by various witnesses and by their own expert due to the entry angle of a fatal bullet wound - 6'5" at least. They send Elena into a bar near the end of the show to meet the Albanian perp who when he arrives is barely average height.
Plot hole: Parker gains access to the external room using a valid security card, they figure out the CEO's passcode which opens the burn room door...and yet the room inside is still protected by a swarm of lasers. Was the CEO supposed to dance through the laser sensors like Parker does every time he goes in?
Factual error: In the opening sequence when Maddie is supposedly driving from Michigan through Ohio and back to Pennsylvania, you can very briefly spot the reflection of a "TD Canada Trust" in the car window. This is because the show is actually shot in Vancouver. In the United States the company is simply known as "TD Bank", which doesn't operate any branches in either Michigan or Ohio. (00:01:55)
Character mistake: Stabler calls for an LPR check on a vehicle. The description of the vehicle he gives is for white Mazda Sentra. Mazda doesn't make a Sentra. Nissan makes the Sentra. (00:09:45)
Revealing mistake: After the Custos's house has been broken into, the next day, the Custos takes a key out of his jacket pocket, unlocks a drawer and takes out a pile of bound papers. When he closes the drawer, he doesn't take the key out of the lock, but he pantomimes his hand returning the key to his pocket.
The Case of the Lucky Loser - S2-E2
Visible crew/equipment: After leaving her husband at train station, Harriet takes a cab to meet a man at a cabin. After a few mins, she takes the man's car to go home. As she drives away, there's a reflection of a man, in suit with glasses (possibly the director) standing offscreen. (00:05:20)
Always Waiting for the Next Bad News - S3-E9
Continuity mistake: Jessica is wearing a massive earring, but when the camera is behind her, she isn't. (00:23:38)
Show & Tell - S6-E10
Continuity mistake: During a conversation with Diane, Jill says that her son is with his dad. In the conversation she calls the dad "Ken." In future episodes Jill's husband is called "Don." (00:03:55)
Character mistake: When Olivia and Dr Galina are in the bathroom, Galina mentions an umbilical chord, from a baby whose mother died (Nadia), that contained Olivia's mitochondrial DNA. Mitochondrial DNA comes from the mother, so Nadia's Mitochondrial DNA came from Letha who got hers from Marie, absolutely nothing to do with Olivia.
Thrill Kill - S5-E1
Factual error: When Dylan gets out of jail, a palm tree can be seen in the background behind him. This reveals that the scene was filmed in Los Angeles, not Philadelphia.
Continuity mistake: In the scene where Karen is about to process the sample from the bathroom the vial is in her right hand and the swab in her left. In the next shot the vial is in her left hand and the swab in her right.
Continuity mistake: When the video of Kimmy plays on the school announcements, and she talks about Duncan being hung up on Veronica, there is a cut to Duncan reacting with raised eyebrows in the foreground, while Veronica can be seen in the background with a passive expression. Then it cuts to a close-up of Veronica having a visible reaction with her whole face falling. But since Veronica and Duncan were reacting to the same thing, Veronica's reaction should have been visible in the first shot as well.
Factual error: In episode 17 there are some scenes showing sick 4400s all around the world. One of them is being carried into an ambulance car in Frankfurt, Germany. The ambulance car's number plate begins with the letters FM meaning Frankfurt am Main. The correct abbreviation for Frankfurt am Main on German number plates is F - not FM.
Continuity mistake: When the professor stands up in the holding cell after Jack tells him that someone saw Skye at 10:30, he slams his chair back causing it to tip over. In the next shot the chair is upright, then when he goes to sit back down, it is again on its side.
Revealing mistake: A recycled shot from an earlier episode causes Bob to enter the room wearing one costume and then suddenly be wearing another when he turns to begin his scene with Dresden and co. (00:11:50)
Continuity mistake: When they first bring the girl to the house with the storm and lay her on the bead the there candles next to her. First the tallest one blows out then the middle one blow out then the shot changes and the middle candle blows out again.
Go Fight City Hall -- To the Death! - S1-E1
Factual error: When Quincy, the well-experienced doctor, uses the defibrillator to bring a just deceased man back to life, he never put some gel on the paddles in the first place. (00:15:25)
Continuity mistake: Just after Sydney gets the book snatched from her by the guy in car, her hands stay near her body and don't move, but in the next shot her hands are thrown out to the side to add a surprised effect.
Continuity mistake: During the test. Light's collar is tucked in his shirt, but a few seconds later it is out.
Visible crew/equipment: When Ned walks upstairs to check on the lady before the bad guy gets killed, behind him is a circular window. A reflecting light can be seen in the window along with what looks to be a boom microphone.