It's a love story between the disobedient student Kang Wook and his teacher Yool Ju set in a high school in Chuncheon. Before meeting Kang Wook, Yool Ju has been dating Tae Hyeon, a public prosecutor. But over time, Yool Ju and Kang Wook fall deeply in love despite social prejudices, an age gap, and a teacher-student relationship. One day, Yool Ju accidentally kills Kang Wook's classmate, who intentionally harasses Kang Wook. But due to narcolepsy, Yool Ju doesn't remember what happened, she fell asleep during the incident. To protect her, Kang Wook goes to jail in her place. Five years later, when Kang Wook is released from prison, he meets Yool Ju again, but she is now engaged to Tae Hyeon. Learning what sacrifice he has made for her, Yool Ju wants to go back to Kang Wook, but this time Kang Wook is not alone - Ja Kyung, his former classmate and currently a radio program host, is by his side. Their circumstances hamper Yool Ju from loving Kang Wook, but she is desperate to help him recover the lost five years and become a top-notch cook.