Imagine a charming person moves in next door and starts flirting with you! A married couple was once very much in love. However, after spending a long time together, they have become indifferent toward one another and are desperately in need of something new. Song Ha is a competent working woman with two children, married to Sun Kyu, a narrow-minded idealist. One day, a couple moves in next door. One is Kyung Joo, a dedicated housewife who is all about housekeeping and supporting her family, and the other is her husband Sang Shik, a patriarchal man. Song Ha and Sun Kyu, who were frustrated with each other, are attracted to their new neighbors, who are totally different from their spouses. What will these couples get up to with their whirlwind of emotions? They have nowhere to run or hide! From romance to sexy comedy, mystery, and even thrilling situations!