'''Airdate:''' May 9, 2010

Deciding to visit Quagmire at his home, Joe and Peter are quickly introduced to Quagmire's father, Lieutenant Dan Quagmire. Immediately turned off by his boring stories, the two soon begin texting each other on their cell phones, and mutually imply that Quagmire's father is a homosexual. Deciding to confront him the next morning, Quagmire decides to invite Peter and Lois to the Naval Ball as guests of his father. The two quickly begin arguing however, with Quagmire insisting that Peter is just jealous because his dad's a drunk and his is a hero. Later that night at the ball, Quagmire is soon bombarded by comments about his father's sexuality from fellow sailors. Deciding to confront his father, Quagmire soon discovers that his father is actually a "woman trapped in a man's body," in desire of a sex change operation. The next day, Quagmire decides to ask Peter and Lois for advice, with Lois suggesting that Peter go along with him to his father's operation. Worried as the operation is taking place, the surgery is announced to be a success, with Dan Quagmire emerging as an attractive blonde woman. Inviting Quagmire and his "new friend" Ida to dinner later that night, Peter soon begins asking her about the surgery. With Lois expressing her embarrassment, Ida reveals that she has no problems discussing the procedure, causing Quagmire to become frustrated, and return home. Deciding to confront him back at the house, Ida and Quagmire discuss their newly altered relationship, with Quagmire left to reject his father.

Meanwhile Brian announces that he will be leaving for a few days to attend a seminar in New Haven about creating your own web series. Returning home to Quahog later that week, Brian decides to stop at the bar on the way home. While there, he comes across Quagmire's father, Ida, and the two quickly bond. Deciding to go back to Ida's hotel room, the two decide to kiss and have sex. The next morning, Brian shares his newfound love with Peter and Lois, and decides to show a picture that he had taken of his new date with his cellphone. Immediately busting out laughing, Brian is left to suggest that they are both jealous because he's found a "real woman", which makes them laugh even harder. Going up stairs to cool off, Brian begins talking with Stewie about Dan Quagmire's sex change. Inquiring about sexual relationships with transgender individuals, Brian learns Quagmire's father's new identity is actually Ida, and [[OverlyLongGag begins vomitting profusely.]] As this occurs, Ida returns to her son's house and decides to apologize to Quagmire, with her son returning the apology. Going on to announce that she found a new boyfriend, Quagmire asks what his name is, and reveals it to be Brian. Quagmire rushes to the Griffin family household and nearly beats Brian senseless, leaving him badly injured. Brian gets the final word, when he says to Quagmire "Hey! I fucked your dad." and shuts the door.

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!!"Quagmire's Dad" contains examples of ([[YMMV/FamilyGuyS8E18QuagmiresDad YMMV goes here]]):
* BigNO: Quagmire upon learning that Ida had sex with Brian.
* ButtMonkey: Poor Brian...
* CluelessAesop: SethMacFarlane said that Ida is meant to be a sympathetic portrayal of a transsexual, but he/she acts like every other gay person on this show (in short, every gay stereotype in the book). Whether you agree with him or not, Seth still sticks by his words, even saying he would have [[UnsettlingGenderReveal reacted the same way Brian would have]] in his situation when questioned about the puking scene.
* DeusExitMachina: Nobody is in the house while Quagmire is beating up Brian, despite the Griffins being there a few minutes before.
** It's lucky for Quagmire the episode ended when it did, otherwise he probably would have lost his friendship with the Griffins for what he did.
* DisproportionateRetribution: The beatdown Quagmire gave to Brian for sleeping, unknowingly, with his newly sex-changed dad.
* FlatCharacter: Ida at her best.
* GettingCrapPastTheRadar: The "phoque" scenes ("phoque" means "seal" [the animal seal] in French, but it sounds like the English word "fuck" with a long "o" sound[[note]]the long "o" sound is the sound heard in words like "alone" and "open" not the "o" sound in words like "hot" and "fond"[[/note]]), which aren't on the TV version, but are on the extended DVD version.
* HypocriticalHumor: Brian is outraged that nobody is asking him about his trip to the seminar, yet turns Meg away when she asks that very question.
** Quagmire's death threat at the end of the episode.
* KarmaHoudini: Quagmire.
* NoHoldsBarredBeatdown and RoaringRampageOfRevenge: Quagmire dishes one to Brian for sleeping with his dad.
* OverlyLongGag: Brian throwing up nonstop for 30 seconds straight.
* PrecisionFStrike: ''"I fucked your dad."''
* ReactiveContinuousScream: Happens between Stewie and Brian following the latter's revelation that that he had sex with Ida, [[UnsettlingGenderReveal who he had just realized was transgender]].
* ShoutOut: Brian scrubs himself in the shower after learning about Ida a la ''Film/TheCryingGame''.
* TenWithATwo: A drunken Brian retiring with Ida to have sex, unaware that "she" was once a he, and was once Quagmire's father, Dan until Stewie reveals the truth.
* UnsettlingGenderReveal: Brian is seriously {{squick}}ed out when he discovers the identity of Ida.