The series focuses on an eccentric motley crew that is the Smith family and their three housemates: Father, husband, and breadwinner Stan Smith; his better half housewife, Francine Smith; their college-aged daughter, Hayley Smith; and their high-school-aged son, Steve Smith. Outside of the Smith family, there are three additional main characters, including Hayley's boyfriend turned husband, Jeff Fischer; the family's man-in-a-goldfish-body pet, Klaus; and most notably the family's zany alien, Roger, who is "full of masquerades, brazenness, and shocking antics."
Roger is forced to sell his beloved attic bar to a restaurant chain after suffering a heart attack, and a sexy new next-door neighbor promises to take Steve and his friends’ virginity in return for housework.
Greg and Terry decide to adopt a 10-year-old Russian boy named Michael. At a party celebrating the decision, Roger is jealous of Greg and Terry's fabulous lifestyle of culture and sophistication. Roger rejects the Smith family as trashy and impersonates Michael, successfully integrating into his new home.
Roger and Francine discover an alien in the woods, and Roger capriciously has a one-night relationship with her before being fed up with her quirks. He tries to get rid of her by calling the CIA, but then realizes that he can’t go through with it.