1999: The Kim family is struggling to move on after their mother, Sunny, vanished a year ago. Sixty-one-year-old John Kim feels more isolated from his grown children, Anastasia and Ronald, than ever before. But one evening, their fragile lives are further upended when John finds the body of a stranger in the backyard, carrying a letter to Sunny. 1977: Sunny is pregnant and has just moved to Los Angeles from Korea with her aloof and often-absent husband. Her loneliness and isolation are broken only by a fateful encounter at a bus stop. The unexpected connection spans the decades and echoes into the family’s lives in the present as they uncover devastating secrets that put not only everything they thought they knew about their mother but also their very lives at risk.

The suspicious death of her mother, Mina, sends Margot Lee digging through the past, unraveling the tenuous invisible strings that held together her single mother's life as a Korean War orphan and an undocumented immigrant, only to realize how little she truly knew about her mother. Interwoven with Margot's present-day search is Mina's story of her first year in Los Angeles as she navigates the promises and perils of the American myth of reinvention. While she's barely earning a living by stocking shelves at a Korean grocery store, the last thing Mina ever expects is to fall in love. But that love story sets in motion a series of events that have consequences for years to come, leading up to the truth of what happened the night of her death.