In 1971 Korea, Soon Yi is an average housewife, whose only hobby is singing. At the time, some 320,000 Korean men are dispatched to fight alongside American troops in the Vietnam War, and her husband, Sang Gil, is one of them. She decides to go to Vietnam to search for Sang Gil by joining a "consolatory band" that cheers up troops. Newly named "Sunny," she embarks on a journey of self-discovery and love.