Crown Prince Sado gets sent to Jeoseungjeon where Gyeongjong the Great and Jang Huibin used to reside due to his father Yeongjo's political ambition. One day, a dead body of an eunuch gets thrown in Crown Prince Sado's room. Crown Prince Sado and Princess Hwawan try to find the culprit but things get more mysterious. Meanwhile, in the middle of the night, the mother of Crown Prince Sado visits Jeoseungjeon to check on her son and happens to witness a big secret...

Seunghui is a pole vault athlete at Daehan College of Physical Education. She had amazing records in the past but she's now suffering from a slump. She even tries to do drugs because she can't jump as good as she did in the past due to her knee problem. She was having a hard time until someone comes to Korea help her. It's Kang Jina, a track-and-field star who was famous worldwide. Kang Jina become Seunghui's coach and they have their special 50-day training together.