[8][9] One day, the 9-year-old son of famous and successful South Korean news anchor Han Kyung-bae, Sang-woo, disappears without a trace.

The police assign detective Kim Wook-jung to the case and assembles a secret investigative task force and forensics team.

The kidnapper, sometimes referred to as the "Bastard's Voice", however, seems to be smarter than any of the detectives assigned to the case: He knows not to stay on the phone too long and keeps changing locations for exchanges.

The police have a number of suspects including Kyung-bae's former best friend Lee Jae-joon who has a grudge on the former for getting him sent to prison, but he has an air tight alibi.

However, the kidnapper is fed up with Kyung-bae's increasingly hostile tone with him, he demands that Ji-sun come meet him at a disclosed location in order to get her son back alive.