ep 127, season 6 (0611) “The Accidental Tsuris” - January 16, 2004
Written by Jeff Greenstein
Directed by James Burrows

Cast: Eric McCormack (Will Truman), Debra Messing (Grace Adler), Sean Hayes (Jack McFarland), Megan Mullally (Karen Walker)

Guest Cast: Geena Davis (Janet Adler), Minnie Driver (Lorraine Finster), John Cleese (Lyle Finster)

When Grace’s rebellious, free-loading older sister Janet comes to town to launch her new jewellery 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.

Resume courtesy of tv.com. Full transcript at Rob Durfee’s “Will and Grace” page