Kim So Eun, a shy high school student who dislikes taking risks, receives a mysterious letter inviting her to the after-school club "Lucky or Not". There, she meets five charming boys who have chosen her as their new leader. Each day, the club randomly selects a piece of paper containing a miraculous and extraordinary mission that the group must complete, revealing the adventurous and daring side of Kim So Eun.

Despite her initial reservations, Kim So Eun's involvement with the club gradually transforms her into a more courageous and bold individual. The unpredictable tasks push her out of her comfort zone, forcing her to confront her fears and embrace the unknown. As she navigates through these thrilling challenges alongside her newfound friends, Kim So Eun discovers a hidden strength within herself that she never knew existed. The "Lucky or Not" club becomes a catalyst for her personal growth and an unforgettable chapter in her teenage years.