His family arranged him to go back to China to study. The ringing of the school bell led to a chance encounter. They both liked piano. The boy, Hao, gave the little girl a "name" and a piano pendant. Gradually, Hao missed the little girl very much and wanted to see this lovely girl again. However, he was disappointed again and again. At a piano competition held by the family, the two met again, but neither of them recognized each other and won the prize. The next day, Hao went to the UK to participate in a piano competition. A week later, Hao received a call from Ling (actually this week, Ling's twin sister suddenly appeared) saying that she must be engaged. Hao fell into the trap. When he was sad, he met a girl arranged by the family, and the two had a new relationship, while Ling didn't know anything. Faced with this cruel sister at home, Ling had been patient and didn't care about her! She has been silently waiting for Hao to come back. In the end, Ling was disappointed and thought that Hao didn't want her. Ling wrote the last diary and committed suicide. Hao returned to China half a year later and found Ling's sister (he thought it was Ling). At the same time, a girl came to the house. It felt very familiar, her? She was the waiter. Under the same roof, slowly, slowly, Hao had an unprecedented feeling for this female voice. Later, by chance, Hao knew that the girl in front of him was 'Angel'...