My Secret Terrius (2018)
A woman named Go Ae-rin (Jung In-sun) loses her husband. Along with her neighbour Kim Bon (So Ji-sub), who was an NIS agent, they discover the truth behind her husband's involvement in a huge conspiracy.
'My Secret, Terrius' is a 2018 South Korean television series starring So Ji-sub, Jung In-sun, Son Ho-jun and Im Se-mi. It was aired on MBC from September 27 to November 15, 2018 on Wednesdays and Thursdays at 21:55 (KST) time slot.