A seemingly ordinary working mother secretly lives as a legendary sniper who delivers justice where the law fails. After returning from a three-year hiatus, she must balance protecting her family with eliminating dangerous criminals, all while a determined journalist and a relentless detective close in on her hidden identity.
The police procedural tackles crimes and clues in the cyber world, weaving a massive, twist-filled mystery of murders, identity switches, corruption and conspiracy.
A team of expert mountain rangers put their lives on the line to save stranded trekkers, solve haunting mysteries and protect Jirisan National Park.

Detectives from the present and a detective from the past communicate via walkie-talkie to solve a long-time unsolved case.
