Mervin Monroe - Dr. Marvin Monroe

Dr. Marvin Monroe is a psychotherapist who first appeared in the first season episode "There's No Disgrace Like Home". Homer pawns the family television in order to afford a session with Monroe for him and his dysfunctional family. The failed attempt at therapy culminates with the Simpsons electroshocking each other endlessly, to the point of causing a blackout. Unable to help the Simpsons, Monroe refunds double what the Simpsons paid, and the Simpsons buy a new TV.

Monroe appears in "Some Enchanted Evening" in which 70% of that episode's original animation had to be redone, although the scenes involving Monroe were mostly untouched, said co-director David Silverman. The script of "Some Enchanted Evening" describes Monroe as "a heavy, chain-smoking, compulsive eater." The original idea behind the character, said Matt Groening, was that he was born Marilyn Monroe and was "very caught up over that", which is why he became a therapist. Monroe's voice is based on psychiatrist David Viscott's. Among Monroe's works is Dr. Marvin Monroe's Guide to Etiquette, which Bart receives as a birthday gift in "Radio Bart".

Since the seventh season, the character Monroe has been retired. This is because voicing the character strained Harry Shearer's throat and, eventually, the voice became too annoying for Groening, which, he acknowledges, is the point. The character's retirement was marked by the broadcast of a Dr. Marvin Monroe Memorial Hospital over Lou's walkie-talkie in "Who Shot Mr. Burns?", Part Two. Since then, several references to Monroe being dead have been made: a glimpse of his gravestone in "Alone Again, Natura-diddily", a Dr. Marvin Monroe Memorial Gymnasium seen in "Bye Bye Nerdie", and a trivia interstitial in the "138th Episode Spectacular" (which was a trick question, as neither Dr. Monroe nor Bleeding Gums Murphy were popular characters). However, Monroe is seen alive in the fifteenth season in "Diatribe of a Mad Housewife" to purchase a copy of Marge's novel "The Harpooned Heart", stating simply that he has "...been very sick" when asked about his absence by Marge.