Eun Jin has been unlucky in her six relationships. With her seventh man she is determined to make it work, even if he is a bit awkward and unromantic. But is he hiding something?

Seemingly an ordinary math teacher in high school, Suk-go is indeed a brilliant mathematician. Hwa-sun is his neighbor. They become inseparable when Suk-go decides to cover up Hwa-sun's accidental murder while she was mercilessly beaten by her ex-husband.

Two African American social scientists pose as bank robbers in an effort to understand the racial dynamics of small-town law enforcement. However, their experiment takes an unplanned, deadly turn.