Who is The Letter From

Jia Yang, in the mist of poverty, bumped into a rival in love from yester years, after a few words of insults, he got to know the real reason of his breakup with his first love during student days, Ge Ying. He went to explain to Ge Ying, but was rejected outside her house. However, by a series of coincidences, Jia Yang went back to school to write his "final love letter". Unexpectedly, the love letter opened a time travel portal, leading Jia Yang to experience a series of differing love journeys, during these journeys, Jia Yang finally understood what his heart truly wants, therefore he bravely pursuing true love, pursuing his journey to the future with resolve.