When Diane gets arrested at a protest rally and has to spend the weekend in jail, John, Alice and Mac are forced to fend for themselves. John quickly becomes overwhelmed, and when he's called away to assume Diane's duties at Meals on Wheels, Alice takes the opportunity to invite popular Karen Field over. Karen's visit soon descends into an out-of-control house party, a situation even Mac can't fix. Meanwhile Diane, who was initially devastated to be away from her family, winds up having a restful "holiday" in jail. In the end, though, she's happy to discover how badly she was missed and needed, and is glad to be home - even if it means having to clean up a serious mess.