Obviously, the standard-bearer of the cliche is Vera, Norm's long-suffering, never-actually-depicted wife. While working at Melville's, the seafood restaurant above Cheers, Vera was glimpsed briefly from the waist-down. On this occasion, she was played by Bernadette Birkett, actor George Wendt's real-life wife.
In "Twin Peaks," FBI Special Agent Dale Cooper constantly records memos intended for an assistant/secretary named Diane, who is never seen. Over time, it becomes questionable whether or not these recordings are actually being transcribed by said secretary, or if they are instead intended as a concentration or problem-solving technique employed by Agent Cooper. Actor Kyle McLachlan later released a series of Cooper's monologues to Diane as "Diane: The Secret Tapes of Agent Dale Cooper," which went on to win a Grammy award.
The producers of "Frasier" hesitated to return to the classic "Cheers" joke about an invisible main character, but ended up doing it anyway by giving Niles Crane an unseen wife, Maris. So many jokes were written at pale, delicate Maris' expense, it soon enough became impossible to even try to cast a real woman in the role. Later, when both "Frasier" stars Kelsey Grammar and David Hyde Pierce appeared on "The Simpsons" (as brothers Sideshow Bob and Cecil), they included a sly reference to Maris.
One of THREE "Seinfeld" unseen characters to make the list, Bob Sacamano is a never-depicted friend of Cosmo Kramer with a lot of bad information, crazy stories and a horrible run of luck. Over the years, Bob suffered from both a failed hernia operation and a case of rabies. His father, Sacamano Sr., is even included at one point, and lives near Jerry's parents in Florida. Sacamano was named for a friend of "Seinfeld" director Larry Charles.
Brasky was the subject of a number of "Saturday Night Live" sketches in which a group of ribald, drunk men celebrate his greatness. "The best damn salesman in the office" or "the best trader in the floor," depending on who you ask, the Brasky sketches - at various times - included cast members such as Will Ferrell and Tim Meadows, as well as guests like John Goodman and Alec Baldwin. In most cases, a mannequin standing in for Brasky appears at the conclusion of the sketch to encourage more drinking and revelry.
On "Diff'rent Strokes," Arnold (the late Gary Coleman) was alternatingly befriended and bullied by the mysterious character "The Gooch." In the memorable episode "Return of The Gooch," bullying inspires Arnold to take up martial arts.
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