The suicide of her best friend, Cheng Ru Ying, ripples through the lives of four mothers – Fang Yuan, Jin Lu, You Xiao Zhu and Ding Mu Mu – as they search for the truth about her suicide. This accident shatters the perfect life of full-time housewife Fang Yuan. When Jin Lu, a non-maritalist curator, is about to realize her career dream, she accidentally gets pregnant and the father of her baby is her temporary boyfriend. The four mothers bravely face up to the twists and turns and search for their initial dreams, and at the same time, they work together to reveal the truth about Cheng Ru Ying's death and to do justice to the dead.

围绕老警察赵鹏程的 “走火” 心结，与青年行动组侦破连环大案、缉拿毒枭徐奎的故事展开。

故事主要讲述了津海市国安局侦察科科长高天阳（韩庚 饰）发现境外情报组织“夜雾”开发了一款名叫“特工任务”的游戏，他们利用玩家在未知情况下暗中开展间谍活动，甚至与高天阳一起长大的弟弟黄子诚（魏大勋 饰）竟也深陷特工游戏之中。黄子诚在游戏的过程中，邂逅了搭档姚瑶（李一桐 饰），两人共同度过一段游戏之旅。正当黄子诚情愫渐生之时，意外发现自己和姚瑶的偶遇，或许并不是一场巧合······游戏的残酷性，一步步显现在众人的面前。高天阳与潜伏在特工游戏中的情报人员吴熙（周放 饰）互相配合，想要破获间谍组织的秘密。误入迷局的游戏玩家该如何脱身？国安人员又将如何逐步粉碎间谍组织的阴谋？