Synopsis of The Big Vent

Will and Grace are freezing because their heat is broken. Will bribes the super to get it fixed, and while they're enjoying the heat coming from the vent in the floor in their living room, they begin to overhear a woman and man talking after making love. Then they hear the woman express her concern that her husband is coming home soon.

The next day Grace is glued to the vent, and Will starts to worry about her when he realizes she came home from work early to listen. Jack comes over asking them to read his play and reminding them that the three of them were supposed to have dinner. They blow him off. He reminds Will about their plans Friday night and leaves. Jack goes to Karen and asks her help with the play. After a casting disaster, Karen tells Jack that his play stinks, and he should write what he knows - stuff from his own life.

Will finds Grace now completely skipping work to listen to the vent. He goes to the laundry room to wash a shirt and meets the people who live downstairs in person. He learns their names and the fact that the man with which the woman is having an affair is the woman's husband's brother. He is now glued to the vent as well. Jack comes over and complains to Will that he was waiting outside for him for the show that they were supposed to see, but he couldn't go in because Will had the tickets. Will is not very apologetic. Will and Grace will not leave the vent.

Will and Grace are gearing up for another night of vent-listening (they think the woman is finally going to leave her husband) when they remember that tonight is the night they are supposed to go see Jack's play. They decide to go, but leave early so that they can listen to the vent. The play turns out to be about Will and Grace not properly appreciating Jack when he was alive, and then drinking poison to join him after he's dead because they miss him so much, and ending up in hell while Jack is in heaven. Will and Grace feel badly for treating Jack so poorly, and take him home with them and cater to his every wish. The couple downstairs listen in.