One day, news anchorman Han Kyung-bae's nine-year-old son, Sang-woo, disappears without a trace. Then the kidnappers nerve-wracking phone threats begin, demanding a ransom of $100,000. When Han's wife, Oh Ji-sun, calls the police, a detective with a secret investigative unit and forensics team takes on the case. Despite their efforts, the cunning kidnapper makes a mockery of them as he slips through their dragnet and tells the parents of new methods to contact him.