Lin Shen can see the countdown above everyone's head. Days, hours, minutes, and seconds, accurate to the very last moment. He has tried to save many people, but has never succeeded. The moment the countdown hits zero, no matter what he does, people die. Over ten years, he watched with his own eyes as three thousand people died, and finally gave up. He no longer looks at anyone's countdown, puts on his hat, and walks with his head down. Until today, when he met someone with no countdown above her head—she herself is zero.