Jiang Yubai died on behalf of Lin Zhao in that accident on a rainy night on campus. Everyone just regarded him as a hero saving the beauty. But no one knew that he had already written his last words in his diary, and even accurately calculated the time when his heart stopped beating. When Lin Zhao tore open his belongings, he discovered that the heart that always secretly took medicine late at night had been beating for him for three years. When school doctor Zhou Yuan's old medical records were dug out, and when Su Tang handed over the blood-stained silver bell, Lin Zhao finally understood that Jiang Yubai didn't save him, but gave his life in exchange for his right to live.