10. Quagmire's Dad
Season: 8
Episode: 18
Original Air Date: May 9th, 2010 Quagmire is excited to get a visit from his father, Lieutenant Commander Dan Quagmire, but right away, Peter and Joe realize that there's something different about the Senior Quagmire. They immediately think he's gay, and confront Quagmire about it, only for Quagmire to tell stories about how tough and manly his father is. That night, upon starting to notice things himself, Quagmire asks his dad about his sexuality, only for his father to say that he is a "woman trapped in a man's body" and how he will be undergoing a sex change operation. The surgery turns Dan Quagmire into Ida Davis, a blonde woman. As someone who has looked up to his father for his entire life, Quagmire isn't too thrilled about the gender switch, and he tells Ida that he doesn't think he can deal with this, causing Ida to leave and check in at a local hotel... where Brian just so happens to be hanging out, on his way home from attending a seminar. Brian has no idea what has gone down in Quahog in recent days, and upon meeting Ida at the hotel bar, goes back to her hotel room for a sexual encounter. After returning home to tell Peter and Lois about his new lady friend, they begin to laugh hysterically. Brian thinks they're just jealous, but upon talking to Stewie, he finds out who Ida actually is, and we're treated to the epic visual of Brian literally puking for 30 consecutive seconds, all while Stewie stands there in amazed horror and eventually taking a step back to avoid the ever growing vomit puddle on the floor. Once Quagmire finds out what happened, he storms over to the Griffin house and begins violently beating Brian, only for Brian to end the episode with one of the funniest single lines in Family Guy history: "Hey... I f**ked your dad."