萧十一郎（严屹宽饰）是江湖中大名鼎鼎的大盗，他同风四娘（李依晓饰）联手，想要盗得失传多年的神器割鹿。沈璧君（甘婷婷饰）是武林盟主沈飞云（王艺曈饰）的女儿，她即将和连城璧（朱一龙饰）订婚，而沈璧君的嫁妆正是这割鹿刀。曾经，年幼的萧十一郎和沈璧君之间有着一段两小无猜的美好时光，如今两人重逢，命运的齿轮就此转动。割鹿刀的存在令沈璧君三番五次陷入危险之中，幸得萧十一郎出手相救，才得以屡次脱险，在此过程中，萧十一郎和沈璧君之间产生了真挚的感情，令铁血冷酷的连城璧怀恨在心，在沈飞云的怂恿之下，他决定除掉萧十一郎。与此同时，魔域宗主逍遥侯（吕良伟饰）亦蓄势待发，企图在江湖之中掀起一场腥风血雨

Xiao Shishilang (played by Yan Yikuan) is a well-known thief in the world. Years of artifacts cut deer. Shen Bijun (played by Gan Tingting) is the daughter of Shen Feiyun (played by Wang Yitong), the leader of the martial arts alliance. She is about to get engaged to Lian Chengbi (played by Zhu Yilong), and Shen Bijun's dowry is exactly this deer-cutting knife. Once upon a time, the young Xiao Shishilang and Shen Bijun had a good time as childhood sweethearts. Now that the two meet again, the gears of fate turn. The existence of the deer-cutting knife made Shen Bijun fall into danger again and again. Fortunately, Xiao Shishilang rescued him and was able to escape many times. Lian Chengbi held a grudge, and at Shen Feiyun's instigation, he decided to get rid of Xiao Shishilang. At the same time, Xiaoyaohou (played by Lu Liangwei), the suzerain of the demon domain, is also ready to go, trying to set off a bloody storm in the arena.