Plot hole: The whole Series 7, episode 5 "Key Party" revolves around Will's 37th birthday. Yet in Series 8, Episode 2 ("I Second That Emotion") Will is talking with Karen at the bar and says "I'm unemployed, I'm single and I'm 41", and four years certainly didn't pass.
Continuity mistake: When Jack is stuck for a special guest on his show Jack-Talk, he surprisingly introduces Grace to be his guest. As she turns around on the sofa and sits down, there is a yellow and brown cushion on the sofa sitting to her right. But in the next close shot of her, it is under her arms as she leans on it. In the next shot the cushion is to her right, sitting on the sofa again. Then as the scene continues, the position of all the cushions on the sofa surrounding Grace keeps on changing! (00:07:20)
Continuity mistake: When Karen is talking to Will at the bar, she is trying to "break down his wall" and starts talking about his relationships. In one shot an extra drink appears on the bar (whisky?), sitting on a red napkin and in the next shot it's disappeared. (00:14:45)
Continuity mistake: When Jack is trying to hush the audience at his show Jack-Talk after bringing Grace onto the show for a follow-up interview, between shots the little bell on his desk moves from his right (near the edge) to over past his left, near the centre of the desk with all the other items. (00:15:55)
The Old Man And The Sea - S8-E3
Continuity mistake: Near the start when Will, Grace and Jack are talking about the new swimming pool, Will starts to peel an orange. In the first shot he peels some of the skin off and drops it on the table. In the next shot there is no peel on the table and he is still peeling it. As the scene goes on, the pile of orange peel on the table that he leaves, keeps changing position. (00:01:30)
The Old Man And The Sea - S8-E3
Continuity mistake: When Jack and Will enter the private swimming pool, there is a large sign barely visible off screen, to the side of a bench. However when they both get in the pool the large sign has now moved to being in front of the bench. (00:05:30)
The Old Man And The Sea - S8-E3
Continuity mistake: At the double date dinner, Malcolm takes a sip of his wine and then Karen starts talking. After Malcolm has put his wine glass down the amount in it keeps changing from almost 1/2 to barely 1/4, back and forth. (00:06:40)
The Old Man And The Sea - S8-E3
Continuity mistake: When Jack is talking to Will at the kitchen area, as Will says "I'm fine, I guess I was just scared", in the first shot he is shaking a bottle of salad dressing. In the very next shot he is now instantly mixing the salad with a pair of mixing spoons. (00:10:00)
The Old Man And The Sea - S8-E3
Continuity mistake: When Will and Jack walk away from the kitchen and Will puts the salad bowl on the table, in the first shot the mixing spoons are both on one side of the bowl, in the next they lay so that one is on either side. (00:10:45)
Continuity mistake: When Will realizes that Grace is eating one of the meals for the homebound elders, he yells at her as she puts the piece of food she's holding in her mouth. But in the next shot the piece of food has reappeared in her hand, then in the next shot her hand is empty again. (00:02:35)
Continuity mistake: When Grace takes Will over to the kitchen and asks him what Clyde is doing at their apartment, in this shot Will puts his right hand up onto the top of the fridge. In the next shot his hand is down on his hip. (00:06:35)
Continuity mistake: When Malcolm enters the steam room, joining Jack and Stan, when he walks forward and says to Stan "I'm sure you've heard all about Karen and I", a huge blast of steam engulfs him (drowning out Stan's reply). In the very next shot all the steam has instantly cleared. (00:12:30)
Continuity mistake: When Grace is talking to Malcolm in her office, in one shot she puts her right hand up on his left shoulder, but in the next shot her arm is by her side. (00:03:30)
Continuity mistake: When Jack is in the carnival tent talking to Will, he sets down the can of Fanta he is holding. In the next shot it has rotated so that what we see on the can is different. (00:11:40)
Continuity mistake: At the end when Will sits beside Jack on the hay, Jack is holding a giant lollipop. When he puts it down on the side next to him, in the following shots its position continues to change. (00:19:25)
Love is in the Airplane - S8-E6
Continuity mistake: When Grace is trying to get in the first class part of the plane, as she talks to the steward her hair keeps changing position from behind or over her right shoulder. (00:01:35)
Love is in the Airplane - S8-E6
Continuity mistake: In one scene as Karen is combing her wig, Jack comes running into the room and as he does, he slides on the large floor rug and causes it to fold up and become wrinkled. In the next wide shot of the room the rug is completely flat and unwrinkled. (00:09:50)
Love is in the Airplane - S8-E6
Continuity mistake: When Will and Grace enter the Heathrow terminal after their flight, Will's hands instantly go from at his side to at his chest between shots. (00:18:05)
Love is in the Airplane - S8-E6
Factual error: When Will and Grace are in the Heathrow terminal, you can see that there are signs which use American terms instead of the British words that would be used; such as "Restrooms" and "Food Court". (00:18:30)
Continuity mistake: When Will and Grace are serving out their dinner, when Grace puts the ladle back into the pot, it changes position from shot to shot. (00:13:00)