Adaptation Sequence: Newspaper Comic —> TV show —> Cartoon —> Video Game —> Movie —> TV show loosely based on movie —> Video Game —> Sequel to movie —> Broadway Musical
Beam Me Up, Scotty!: Morticia is often quoted saying, "Normal is an illusion. What's normal for the spider is chaos for the fly." However, no one is sure when exactly she said that.
She does say the line in The Musical, but it seems to be a reference to the presumed earlier quote.
Keep Circulating the Tapes: To this day, there has never been a DVD release for the following Addams Family films and shows: The Addams Family Fun-House, Halloween with the New Addams Family, the 1992 animated series, Addams Family Reunion, and — at least in America — The New Addams Family (the latter being caught between Saban and Disney- what else would you expect from a Fox Kids/Fox Family show?).
One Normal Night: From the song of the same name in the 2010 Broadway musical, where Wednesday, hoping to set a good impression with her fiance and his family, requests that the Addams clan try to behave like average human beings. As expected, they can't, and Hilarity Ensues.
What Could Have Been: After Illumination Entertainment obtained the rights to Charles Addams' original cartoons, there was a planned stop-motion animated film with Tim Burton calling the shots. As of July 2013, the project has been cancelled.
For the various television serieses:
Actor Allusion: The 1960s TV episode "Morticia The Breadwinner" contains one to Morticia's actress, Carolyn Jones, whereupon Morticia and Uncle Fester are deciding on a good assumed name they can use to call Gomez's stockbroker: 'Jones?' asks Morticia. 'What kind of a name is that?!' replies Uncle Fester irritably.
Disowned Adaptation: Though he visited the set a few times, Charles Addams considered the original series a travesty. One must wonder how he would've felt about the film adaptations had he lived long enough to see them (he died in 1988).
Dueling Shows: With The Munsters. The Addams family were humans that acted like monsters, but the Munsters were monsters that acted like normal humans. It was an interesting contrast.
Fake American: The entire cast of The New Addams Family (apart from Glenn Taranto and Nicole Fugere, who played Gomez and Wednesday, respectively) were Canadian.
A sort-of example from the series: the man playing Thing occasionally used his left hand just to see if anybody would notice.
Jane Rose replaced the ailing Blossom Rock as Grandmama for Halloween with the New Addams Family.
The Other Marty: In the original series, Thing was usually performed by Ted Cassidy; whenever a scene required both Thing and Lurch to appear together, a stagehand (usually associate producer Jack Voglin) would take Cassidy's place while he performed instead as Lurch.
Recycled Script: Most of the episodes of The New Addams Family were recycled from the original series. In fact, the episode "Thing is Missing" is a twofer. Not only is it a remake of an episode from the original show, but it also borrows two plot elements from the 1992 animated series episode "Itt's Over" (though this time, Uncle Fester starts growing hair because he's stressed over the mistaken belief that Thing is dead rather than Cousin Itt).
Self-Backing Vocalist: Composer Vic Mizzy, who couldn't afford singers, triple-overdubbed his voice for the theme song to simulate a trio.
Throw It In: Ted Cassidy ad-libbed "You rang?" in the pilot, and the producers kept it — and changed Lurch from a mute to allow for it.
The series was originally going to be from Lurch's perspective (though he wasn't named at the time), and John Astin was actually called upon to audition for the role, leading to him almost backing out of the series until the idea was reworked.
Charles Addams, who provided names for the characters when his creation went to series (they were unnamed in his cartoons, even lacking the "Addams" surname), initially submitted the name "Pubert" for the family son. Producers rejected it on the basis that it was too vulgar, leading him to come up with "Pugsley" instead. The name Pubert would, of course, go on to appear elsewhere in the franchise (see Development Gag below).
Chaz came up with two different names for the family patriarch, and left the final choice up to the character's actor, John Astin. Imagine how different the show could've been had Gomez instead been named "Repelli".
Halloween with the New Addams Family was intended as a quasi-pilot for a TV series revival, but for one reason or another the idea never got off the ground.
An early teaser trailer for the first movie begins with footage of another film that's being played in a theater. The character in the film turns and screams at something in the audience. As everyone turns back to look, it is revealed that the entire family is occupying the back row, and they snap their fingers in time to the theme music before the teaser ends. This sequence was shot specifically for the teaser, and features Christopher Lloyd in early makeup for Uncle Fester.
Addams Family Values' teaser trailer has a nurse examining babies in a maternity ward, all while adoring parents look on behind glass. She comes to a crib that's covered in a massive black overhang and opens it up to examine, then turns around and screams once she sees what's inside. Like the original, this clip was shot specifically for marketing purposes, and never appears in the final film.
For unknown reasons, Carol Kane replaced Judith Malina as Grandmama for Addams Family Values.
The third movie did this to most of the actors playing the family. Justified, as it's intended as a separate continuity, and the only reason it exists is to have served as the Pilot Movie for The New Addams Family.
Playing Gertrude: Carol Kane is 26 years younger than the actress she Darrined, making her younger than either Huston or Julia.
Wag the Director: According to director Barry Sonnenfeld, in the first film, Gordon Craven wasn't supposed to have been Fester all along, but still an imposter, though the family would've accepted him as Fester anyway, as, in Sonnenfeld's words, "...family wasn't about blood, it was about love." Sonnenfeld described Anjelica Huston as "passionately against" the idea and Raul Julia as "outraged" (though funnily enough Christopher Lloyd himself didn't care either way), and in the end, the cast chose ten-year-old Christina Ricci to convince Sonnenfeld to change the ending.
According to Larry DeMar, The Addams Family was originally designed with alphanumeric displays (instead of the then-new dot matrix displays), feeling that the dot matrix display's budget would be better spent on other parts of the game.