Dedicated to her single lifestyle, level 7 government worker Jung Ha-na finds herself assigned to the new Marriage Promotion Team at work. Faced with the irony of promoting marriage as a non-believer in it, she sees only one escape: get island bachelor Bong Cheol-hee married. Determined to accomplish the mission, Ha-na heads to Cheongdo in search of this mysterious man, hoping it's her way out of the Marriage Promotion Team.

Ha-na's mission to leave the Marriage Promotion Team becomes urgent when her ex-boyfriend, Ki-jun, shows up as her new team leader. Determined to escape, she focuses all her efforts on setting up Cheol-hee's first blind date. Meanwhile, In-ah crosses paths with a mysterious man who saves her in a dangerous situation, sparking the beginning of a fateful encounter.

In-ah applies for the Marriage Promotion Project in hopes of being matched with Cheol-hee. The Marriage Promotion Team is shocked by the third-generation chaebol's interest in an island bachelor, but Ha-na worries about the differences between the two. Meanwhile, Cheol-hee grows curious about the past connections among Ha-na, Ki-jun, and In-ah, as new tensions unfold in their interactions.