Jack suffers Karen's wrath when he is seduced into friendship with her manipulative British romantic rival, who has set up house with Karen's ex-husband. Meanwhile, Will and Grace try to re-connect their lagging friendship with a competitive night of board games with their friends.

In the middle of her divorce proceedings, Karen learns that ex-husband Stan has suddenly passed away, and the funeral becomes a contest of wills between Karen and her British rival, and a free-for-all when the will is read for everyone who ever felt deserving, such as Will. Meanwhile, Grace is shocked when recently returned husband Leo is called back into service by Doctors Without Borders and asks her to make the trip with him to Guatemala.

Karen, Will, Jack, and Grace go on a trip in Karen's yacht to sprinkle Stan's ashes into the Caribbean while Leo is flying to Guatamala with an atractive co-worker. While Karen sprinkles Stan's ashes she finds Lorraine has been stowing on board. While Karen and Loraiinne fight, Will and Jack get drunk. Lorainne pushes Karen off the board and Rosairo jumps off after her. The next morning Grace finds Leo's bag with a letter from his co-worker Danni saying that she wants Leo. Will wakes up in bed naked with a hangover and a naked Jack in the bed with him. Meanwhile Karen and Rosairo are stuck on a cargo boat.

When Grace's rebellious, free-loading older sister Janet comes to town to launch her new jewelry enterprise/folding table subway stand, Grace decides to put her foot down casting her sibling away. However, when her tough love prompts Janet to go corporate by taking a 9-5 job and studio apartment, Grace can't seem to handle her new image. Meanwhile, Karen continues to spurn Lyle's proposals of marriage, only to have a change of heart after Lorraine stops by for an impromptu visit, to declare her disapproval over Karen's ""relationship"" with her father.

Dynamic enterprisers Will and Grace begin a new business venture as they buy old apartments to refurbish and re-sell for a tidy profit. When budding ""student nurse"" Jack bumps into his former acting mentor Zandra, the pair of entrepreneurs finds their first project apartment. Meanwhile, Karen renews her romance with Lyle Finster, but the couple's bliss is interrupted by an unfortunate houseguest when Lorraine moves in.

Enjoying the success of their new business venture, entrepreneurs Will and Grace help their apartment buyers Jack and Stuart settle into their new life under one roof. However, when Grace receives a higher offer on the apartment, the ""friendly flippers"" attempt to break up the happy couple by encouraging Jack's cold feet as they see a chance to make a quick buck. Meanwhile, Karen demands that Lyle finally discipline his unruly daughter Lorraine, nearly shattering the couple's budding romance.