After being denied a weekend getaway with Barry due to the stories he's told about his family, Steve hatches a plan to actually introduce them, in the hopes that they will hit it off and allow the pair to hang out more. Stan and Francine reluctantly attend a dinner, where they are completely wowed by Ted and Connie and their 1970s style. But when Steve excuses himself to use the restroom, he accidentally stumbles into a bedroom where he finds that not only are Connie and Ted into swinging, but intend to swing with Stan and Francine.
Steve finds that Barry is used to this sort of behavior and they are quickly shuttled off to his treehouse so that the adults may be alone. Steve manages to escape and breaks his arm in the process, which allows him to interrupt the night. Talking with Hayley the following day, she predicts that the end result will be divorce. Steve tries to demand that his parents never see Ted and Connie again but finds they've already adopted their sense of style. He throws his weight around by threatening their internet passwords and sends them to their room, but later finds they've escaped and gone to the Turgid Springs Nudist Resort. Enlisting Barry to help sneak into the resort, they catch up with the foursome. But when he drops the news that Ted and Connie are swingers, Stan and Francine are already aware of this, having been informed on the first night and already established that they would not participate.
Later that night, Steve asks Barry where everyone is so he can apologize, but finds that not only has Berry reverted to his evil state, but that everyone swings at the resort, whether they intend to or not. After Barry provides a little exposition to explain that the haste of the trip caused him to miss his medication and revert to his evil self. He further explains that because Stan and Francine refuse to let them hang out, he is determined to break up their marriage. Having enticed everyone to the steam room, he has placed a powerful aphrodisiac in the steam, so they will have sex rather they intended to or not. Betrayed, Steve 'goes bananas' and, evading several gunshots from Barry before taking him out of action, rushes to the steam room where he finds everyone in post-sex bliss. Stan admits that they all had sex, but only with their own partners and sticking to their principals. Grossed out, Steve decides to wait in the car.