警察童明松（祖锋饰）负责调查一起车祸案件，一名大学生蚊子（常方源饰）意外惨死，让整个案件充满了谜团。童明松决定与好友兼蚊子的喜欢者、修车工秦枫（朱亚文饰）一起揭开事件背后的真相。在他们追查真相的过程中，却渐渐卷入了中产阶级夫妻乔永照（秦昊饰）和陆洁（郝蕾饰）的故事。陆洁因为女儿在幼儿园结识了宇航的母亲桑琪（齐溪饰），然而在与桑琪交往的过程中，她发现了丈夫的外遇…

随着调查的深入，童明松和秦枫发现乔永照、陆洁、桑琪三人都隐藏着不可告人的秘密。这些秘密逐渐浮出水面，让整个事件变得更加扑朔迷离。每一个人都似乎有着自己的过去和不为人知的一面，而这些隐藏的真相将会如何影响他们的生活？

Police officer Tong Mingsong (played by Zu Feng) is in charge of investigating a car accident case. A college student Mozi (played by Chang Fangyuan) died unexpectedly, which made the whole case full of ambiguity. up the mystery. Tong Mingsong decides to uncover the truth behind the incident with his friend, mosquito lover and car repairman Qin Feng (Zhu Yawen). In the process of tracing the truth, they gradually became involved in the story of middle-class couple Qiao Yongzhao (Qin Hao) and Lu Jie (Hao Lei). Lu Jie met Yuhang's mother Sang Qi (played by Qi Xi) because of her daughter in kindergarten. However, in the process of getting along with Sang Qi, she discovered her husband's affair..

As the investigation deepened, Tong Mingsong and Qin Feng discovered that Qiao Yongzhao, Lu Jie, and Sang Qi were all hiding secrets. These secrets gradually surfaced, making the whole incident more complicated and confusing. Everyone seems to have a past and a side they don't know, and how will these hidden truths affect their lives?