沈十五在一次阴差阳错的经历中爱上了王诗诗，夜晚变身成的月儿，可是他已经和王诗诗有了婚约在身。而刘星雨也对王诗诗一见钟情，王诗诗是当时京城的第一艺妓，三个人被蒙在了鼓里，展开了一段奇妙又浪漫的感情经历。随后，在他们前世今生慢慢的被揭露开来的背景下，沈十五和刘星雨分别被妖界妖后明珠，还有月秦国的公主耶律谷儿产生了情感的交割，可是不久之后，当世间变得混乱，各个族群相互混战时，为了天下苍生和世间大爱。他们肩负起了责任和正义，携着神剑鸣鸿，惩恶安邦，拯救了天下。在最后天下平定下来的时候，三个人也终于解开了谜团，王诗诗就是月儿，而沈十五和王诗诗是有婚约的，他们如期完婚了，刘星雨也心甘情愿的祝福着他们

Shen Shiwu fell in love with Wang Shishi in an accidental experience, and transformed into Yue'er at night, but he already had an affair with Wang Shishi. I have a marriage contract. And Liu Xingyu also fell in love with Wang Shishi at first sight. Wang Shishi was the number one geisha in Beijing at that time. The three of them were kept in the dark and started a wonderful and romantic emotional experience. Later, under the background that their past and present lives were slowly being revealed, Shen Shiwu and Liu Xingyu had an emotional exchange with Pearl, the queen of the demon world, and Yeluguer, the princess of Yueqin, respectively. The world becomes chaotic, when various ethnic groups fight each other, for the common people of the world and the love of the world. They shouldered responsibility and justice, carrying the divine sword Minghong, punished the evil Anbang, and saved the world. When the world finally settled down, the three of them finally solved the mystery. Wang Shishi was Yue'er, and Shen Shiwu and Wang Shishi had a marriage contract. They got married as scheduled, and Liu Xingyu also wished them well