This prequel will show an “untold story” that viewers couldn’t see from the original episodes, and it will specifically focus on the Doldam Hospital. Gang Dong-ju and Yun Seo-jeong have their final pictures taken together as they spend their last few days together at Doldam Hospital. The letter's contents are finally revealed, which changes everything for the couple again. They're both set to their new adventures, and Teacher Kim gets the break he deserves in a long time. Teacher Kim meets a beautiful face in an unexpected place.