Main •
Bae Suzy as Lee Yumi / Lee Anna • Kim Soo-in as 14-year-old Yumi • Choi So-yul as 6-year-old Yumi : A woman who loses her true identity and starts living a new, unpredictable life under a new name because of a minor lie that she made up. •
Jung Eun-chae as Lee Hyeon-ju : Yumi's former boss. Born in to wealthy family, she runs a gallery owned by her father where Yumi was a terminal employee. •
Kim Jun-han as Choi Ji-hoon : Yumi's husband. An ambitious, goal-oriented man. He is the CEO of a promising venture company, his own business he started at a young age. •
Park Ye-young as Ji-won : Yumi's only confidante. A senior in the editorial department of a university school magazine.
Supporting •
Kim Jung-young as Hong-joo : Yumi's mute mother. • Choi Yong-jin as Lee Sang-ho : Yumi's father, a tailor. • Heo Hyeong-gyu as Kang Jae-ho : A college student Yumi dated while she was pretending to be a college student. •
Woo Ji-hyun as Seon-woo : An employee at a restaurant owned by Hyeon-ju. •
Kim Soo-jin as Chief Kim : An employee at Hyeon-ju's company who took care of Yumi. • Oh Man-seok as Mr. Lee : Hyeon-ju's father and owner of the gallery where Yumi worked. •
Baek Ji-won as Hyeon-ju's mother : The director of the gallery where Yumi worked. •
Yoon Ji-min as Professor Yoon • Hong Hee-won as Secretary Jung • Chu Kwi-jung as Jae-Ho's mother • Jang Ha-eun as Narae, student at Yale University. • Lee Je-yeon as Music teacher • Park Soo-yeon as Secretary Cho Yu-mi == Production ==