When the wind is calm and the sun is shining, the lake surface is like a mirror, calm and serene; under violent storms, the lake surface will raise waves, angry and violent, as if to tear everything into pieces. However, the lake water changes with the changes of nature. Despite experiencing hurt, anger, ruthlessness, betrayal..., After Qianfan has passed, the lake water still returns to tranquility and remains the same. As for the human state of mind, after experiencing all kinds of things, can it be like the lake water, watching in place with the original sincerity. The four people's innocent friendship and deep feelings began on the university campus. For various reasons, they had to separate and wait for eight years of love. Whether we can continue after reunion, time is passing, the environment is changing, and whether people's hearts can stay at the beginning. From the beginning of a last resort to cherish, a brave confession of uncontrollable emotions, to a life-long entanglement of pure and true love that is unwilling to reach out to grasp. What exactly is it for?