The Miura and Kanzuka couples, who live in the same apartment building, have made it a tradition to have a barbecue on the rooftop once a month. It was also customary for their wives, Ayumi and Ayako, to vent about their husbands during these gatherings. A few days later, Ayumi gets into a trivial argument with her husband and storms out of the house, saying she's going back to her parents'. Unable to watch Ayumi like this, Ayako suggests a temporary couple swap for a few days to cool off and mend their relationship. However, this couple swap leads to unexpected mistakes...