Continuity mistake: During dinner, items on Frank and Charlie's table move around, for example, the pepper shifts, most noticeably when the house wine is brought over.
Continuity mistake: During rehearsal when Artemis agrees the song shouldn't be cut, her hand is on Charlie's shoulder. When the camera cuts, she's standing away from him with her arms to her side.
Continuity mistake: When Dee is standing up she is smoking a cigarette with her right hand. When the shot comes back to her as she cuts Charlie's joke off, the cigarette has disappeared and the bottle of whiskey has left the table and is in her right hand. (00:01:15)
Dennis and Dee Get a New Dad - S2-E10
Continuity mistake: When Dee tells the gang someone is contacting her claiming to be their dad, only one coffee cup is next to Dee, on the side closest to Mac. She lifts that cup and puts it towards her lap, but when the camera shows the computer, the cup is back and another cup is on the other side of the computer. When the camera zooms out both cups are gone again. (00:00:30)
The Gang Runs for Office - S2-E8
Continuity mistake: When Mac is sitting in the back of the cop car and the black cop is talking about how people don't take kindly to being called a nerd, there is a red car driving up behind them. When the camera pans out it has become a white SUV. (00:21:40)
Paddy's Pub: The Worst Bar in Philadelphia - S4-E8
Continuity mistake: In the scene when the gang opens the trunk to reveal the first kidnap victim, Sweet D is wearing black nail polish. The next scene in the apartment her nails are not black anymore. Then in the next trunk scene with the second victim they are black again.
Bums: Making a Mess All Over the City - S3-E14
Factual error: Charlie drops the moltov cocktail into the police car in the end, light enough so that it doesn't break, but the car explodes about ten seconds later, as Charlie explains he had soaked the entire inside with gasoline. However, there realistically wouldn't be such a long pause as shown in the show for the gasoline fumes to ignite. Also, the explosion is much more powerful than it realistically would have been, revealing pyrotechnics were used. Obviously done for comedic value, but still a mistake.
The Gang Gets Invincible - S3-E2
Continuity mistake: When Mac and Dennis are talking to Doyle on the bus, watch the background outside of the window. Every time the camera cuts back and forth, the background changes. The most noticeable change is near the end of the scene, when the background changes from trees and shops passing, to suddenly the side of a bridge passing.
Continuity mistake: In the opening scene, as the gang is being mugged, watch the background. Towards the end of the scene, there are suddenly three cars parked on the street behind the gangs after a brief cut to the mugger, despite there having been no time for them to all appear.
Continuity mistake: When we see Mac and Dennis smash the boards successively over Charlie's back, as the camera cuts to a closeup of Charlie, Dennis suddenly appears behind him, despite the fact he already smashed his board and walked off-camera.
Bums: Making a Mess All Over the City - S3-E14
Continuity mistake: At the end of the episode, when Charlie leaves the envelope marked "4 the Mare" outside the Municipal Building, as he walks away we see a janitor come by and throw the envelope away. However, seconds later when Charlie jumps into the air, we see the janitor walk and bend to pick up the envelope again.
Continuity mistake: When Dennis is showing Dee the photos of his male selections, the order of them changes after the camera switches to Dee's face. (00:06:11)
The Waitress Is Getting Married - S5-E5
Continuity mistake: At the bachelorette party Dee holds, Charlie's mother says she needs a ride and falls back on the couch with her head down. The shot cuts to Dee answering the door, and Charlie's mum's head is back up at a different angle.
Frank Sets Sweet Dee On Fire - S3-E8
Audio problem: When the gang goes down to Chinatown, Mack is reporting that the crowd is about to do martial arts. The screaming audio in the background has been looped at least three times.
The Gang Makes Lethal Weapon 7 - S15-E2
Audio problem: When Dennis is talking about the dates he has been on whilst in the bathroom, after the third date is shown, he says, "This generation doesn't even understand half the shit that they're saying." Whilst saying the line, the camera cuts to focus on the others, and Dennis' mouth can be seen in the corner of the frame, but the movements of his mouth don't appear to match the audio. (00:17:40)
The Gang Goes to Hell - S11-E9
Continuity mistake: Dee tells a woman on deck that a chair is hers. The woman shows that she already has a towel on the chair. Suddenly, her towel is fully laid out on the chair when she goes to sit down. At no point do we see her put the towel on the chair like it ends up.
Charlie Catches a Leprechaun - S11-E8
Continuity mistake: Dennis is holding a tablet with a kickstand at the beginning of the episode. In one angle, you can see that the kickstand is out. In the rear shot, it's flat against the tablet.
The Gang Goes to the Jersey Shore - S7-E2
Visible crew/equipment: When Dee and Dennis are walking across the beach, the shadow of the camera can be seen on Dee's stomach. (00:03:55)
Continuity mistake: Dee's position on the airport carousel changes. She's going through the door in one shot, and then she's further out. Then, in the final shot, she goes through the door again.
Charlie's Mom Has Cancer - S8-E6
Continuity mistake: P-Diddy's glasses appear and disappear when we first see him.
