Boo! Humbug is the fifth episode of the first season.
A Kids' Holiday
Jack invites Will and Grace to Halloween but they refuse to go saying it's a kids' holiday. Before Will and Grace can start their movie night, Harlin drops by and leaves his children with Will for the night. They realize they have nothing child-friendly in the apartment so they have no choice but to take them out trick or treating.
Body and Soul
Jack then invites Karen who had never gone downtown on Halloween. They go as "body and soul" i.e. Karen in a revealing outfit and Jack as David Soul in his Starsky & Hutch character. On the streets downtown, Jack's friends mistake Karen for a well-dressed drag queen and earns herself a squad of drag queens.
- Eric McCormack (Will Truman)
- Debra Messing (Grace Adler)
- Sean Hayes (Jack McFarland)
- Megan Mullally (Karen Walker)
- Gary Grubbs (Harlin Polk)
- Paul Goebel (Jerry)
- Ben Caswell (Sam)
- Reiley McClendon ("Nixon")
- Jorden Ashley ("Buzzy Wuzzy")
- Michael Stadvec ("Starsky")
- Demitri Corbin (Drag Queen #1)
- Terrence Michael (Drag Queen #2)
- John Cantwell (Drag Queen #3)
- Title refers to the famous line uttered by the character Ebenezer Scrooge on A Christmas Carol, "Bah! Humbug", to express his disgust regarding Christmas. "Boo" is a popular exclamation for scaring people, hence making a reference to the Halloween season.
- Karen's stepchildren's names are first mentioned.
- Karen's drag name is Shu-Shu Fontana and Jack's is Glen 125th.
- Jack does his Cher impression for the first time.
- Grace sees Will's Shirley Maclaine's Inner Workout tape, and he says he will respond in his "next life". Maclaine's programs are about relaxation and the New Age philosophy of reincarnation.
- Will and Grace plan on spending Halloween night watching Ingmar Bergman movies. Bergman was a Swedish director who gained worldwide fame in films such as The Seventh Seal (1957) and Cries and Whispers (1972), mainly dealing with existential questions of mortality, loneliness, and faith.
- When Harlin's children were taking off their masks, Will says that for a second he thought the one wearing Nixon's mask would be Gerald Ford. Ford was Nixon's vice-president who took on the presidency after Nixon resigned in 1974.
- Karen gets her dragname by taking the name of her first pet and the first street she lived on. This is a popular formula on how to get an alias, usually in adult films.
God can hear you right through the building, and she's not happy. — Jack, After Grace says Halloween means nothing to her
Have a good time. And remember, wear reflective tape, get lots of candy, and don't put anything in your mouth that isn't wrapped. — Will, To Jack on Halloween