Go Ae Rin (Jung In Sun)’s husband dies suddenly, leaving her a single mother to her two children. Meanwhile, in the apartment next door lives Kim Bon (So Ji Sub), a.k.a. Terrius. Once one of the most highly skilled special operatives agents in the National Intelligence Service, three years ago he dropped off the grid, and went into hiding after the woman he loved was mysteriously shot dead in a botched special mission. Alone, he has been attempting to piece together what happened, careful never to reveal his whereabouts to anyone. But when he meets Go Ae Rin, the two realize that they have a shared goal – to uncover the truth. The duo decides to form an unlikely alliance and investigate what happened to the people they loved. What they begin to unearth, however, is that Go Ae Rin’s husband was sucked into part of a huge conspiracy that goes a lot deeper than either of them could have possibly imagined… “My Secret Terrius” is a 2018 South Korean drama series that was directed by Park Sang Hun.