Will & Grace (1998) - 4 mistakes in "Alley Cats"

Continuity: When Rob & Ellen are confronting Grace about how competitive she is, there are several shots of them from the same angle. In some shots there is a red bag visible in the bottom left corner, in others it disappears.

Continuity: Grace unpacks her Scrabble board game from her bag, and puts it on the table, and puts the bag on the floor. Then her friends tell her she is too competitive, so she goes to her bedroom. As she goes, you can see that the board game on the table has now been replaced by the big red bag.

Revealing: When Will goes to pour himself a glass of whiskey, the brown liquid that is chosen to represent the liquor has foam bubbles on the top of it that resemble the ones that soda has.

Plot hole: In the bowling alley scene, Ellen states that Grace would need to knock down 27 pins in order to tie. Will and Grace then have a conversation, and Grace gets a strike with her next ball. They then start gloating that they have beaten Rob and Ellen, but the scores don't add up, and they couldn't go into the lead on that round.