Continuity mistake: When Bertram climbs through the window into Stewie's bedroom, just as he tiptoes past a sleeping Stewie, the lightswitch on the wall is in the up position and the room is dark, but two shots later Stewie wakes up and now the lightswitch is in the down position so Stewie flips it up, then the light turns on. (00:10:20)
Continuity mistake: When Bertram sneaks into Stewie's bedroom, he tiptoes past Stewie, who is sleeping. But in the next close-up of Bertram, the shot pulls back and pans the room so we see Stewie's crib is empty. But in the next shot, Stewie is still sleeping, and then he wakes up. (00:10:25)
Continuity mistake: When Brian and Stewie arrive in Leonardo's atelier, we know that they are in Florence for two reasons: because of history and because we see Palazzo Vecchio (which is in Piazza della Signoria, in Florence) outside the window. Then, when Stewie and Bertram are fighting with Leonardo's flying machine, the city of Florence is wrongly represented as if it were Venice, with the sea, the lagoon, and the canals.
Continuity mistake: While Lois is in the Paris hotel suite packing her suitcase there are two doors behind her, and Bonnie opens one of those doors. The other door has its door knob on the left side of the door, but when Lois walks over and opens that other door to reveal Joe, its door knob is now at the right side of the door. (00:18:00)
Continuity mistake: At the start, while Peter and the kids are watching TV, the buttons on Peter's shirt are on his left side, but in Peter's closeup the buttons switch to his right side, where they usually are. The switching happens again in following shots.
Episode VI: It's a Trap - S9-E18
Continuity mistake: In S8xE20, "Something, Something, Something, Dark Side," when Han was frozen in carbonite he was smiling with head turned toward his right side, but in this episode, after Jabba watches Luke's message, Han's carbonite is hanging on the wall and now Han is smiling with his head turned toward his left side. (00:05:10)
Episode VI: It's a Trap - S9-E18
Continuity mistake: When Leia frees Han, the buttons she pushes to free him change repeatedly.
Episode VI: It's a Trap - S9-E18
Continuity mistake: Luke's handcuffs disappear when he almost falls into the pit.
Episode VI: It's a Trap - S9-E18
Continuity mistake: When C-3PO says "Oh My God!", there's a Greedo-like alien on the stairs, but when R2 plays the message about Luke, the alien is no longer there.
Continuity mistake: Near the end of the episode, Joe and Quagmire are shown sitting at a booth inside the bar with Joe pulled up to the corner of the booth. As Peter apologizes to them, Joe is no longer seen next to him. As Peter takes Quagmire's check, a part of Joe is seen sitting in the next booth. In the shot after, he disappears again for the rest of the scene.
Seahorse Seashell Party - S10-E2
Continuity mistake: Brian cuts his entire ear off. The top of his ear reappears a few shots later.
Screams of Silence: The Story of Brenda Q - S10-E3
Continuity mistake: When Lois and Brenda are out eating, Lois closes her menu when the waiter comes by. But the next shot of her menu it's open when we don't see her touch it.
Screams of Silence: The Story of Brenda Q - S10-E3
Continuity mistake: When Brenda arrives at her intervention, she sits down and puts her purse on the floor. It disappears for the rest of the scene.
Screams of Silence: The Story of Brenda Q - S10-E3
Continuity mistake: Throughout the entire intervention scene you can see Brenda's hands. After her boyfriend starts talking he says they are getting married. Brenda holds up her hand to show her ring and suddenly there's a splint on her finger.
Screams of Silence: The Story of Brenda Q - S10-E3
Continuity mistake: When Peter and Joe find Quagmire hanging from the ceiling, he has 2 black eyes. Minutes later in the hospital, they look normal.
Stewie Goes for a Drive - S10-E4
Continuity mistake: Stewie packs his backpack, opens the window and slides down the drain pipe. When Brian comes in to get him, the window is closed, but Stewie didn't do it.
Continuity mistake: When Peter (from 1999) arrives at Quagmire's house for the stag party, the window is small. But in the next shot when Brian looks through the window, it is a lot bigger. (00:05:55)
Continuity mistake: In the scene with the multiple versions of Stewie and Brian come back to 1999, one Peter is with one of them. When Stewie asks everyone to vote between 9/11, Peter is standing in the foreground, but disappears when one of the Stewies says Brian had his throat slit. (00:18:25)
Continuity mistake: Kevin takes his jacket off at the dinner table. His shirt says Ed Hardy. The name wasn't on the shirt until he took his jacket off and it disappears again when he puts the jacket back on.
Continuity mistake: Quagmire and Meg are sitting on the couch. From out of nowhere he gives Meg a gift for her birthday. He came over empty handed.