Based on the 1987 movie, Overboard, starring Goldie Hawn and Kurt Russell, MBC brings us the story of Anna Jo (Han Ye Seul), a rude, feisty, and audacious American-bred heiress who can never be satisfied. She returns to Korea only to continue being a controlling wife to her already cowardly husband, Billy Park (Kim Sung Min). When her yacht gets stuck for repairs, she hires local handyman Jang Chul Soo (Oh Ji Ho) to fix her shower, but when they have a heated spat over her dissatisfaction and lack of payment, she pushes him overboard and dunks his tools into the ocean right along with him. Later, after a quarrel with Billy that threatens to end their marriage, she herself gets drunkenly pitched overboard and falls victim to a bad case of amnesia. But in the hospital, she ends up beside none other than Jang Chul Soo, who’s still recovering from his own swim in the ocean for his lost tools. Unknown to her, he's been raising his three orphaned nephews in their unkempt house and desperately needs a nanny. Taking advantage of her memory loss, he manages to convince her that she's his live-in girlfriend and renames her Na Sang Shil. But he didn't expect her spoiled selfishness to slowly turn into compassion. And he didn't expect to fall overboard again—this time, for her.