"Return to the Ancients: Destiny and Cause and Effect" is an epic story that combines fantasy, adventure and destiny. It tells the story of the protagonist Chen Xuan's legendary experience in fighting against the forces of chaos with his wit and courage after traveling to the mythical world of ancient times. Chen Xuan was originally an ordinary office worker. He accidentally traveled to ancient times when he clicked on a mysterious advertisement while working on a project all night long. He found himself in a different world full of dangers. The back of his head was injured, and the surrounding environment was strange and full of danger. In the process of escaping, he discovered the translucent line of cause and effect, and gained mysterious abilities by killing the three-eyed creature. Later, he obtained the Karma Compass and embarked on a journey that would change his future destiny. Chen Xuan was chased by the Blood Scale Clan, fainted while fleeing, and was rescued by Wuchang Taoist. Taoist Impermanence told him the truth about the prehistoric world and the importance of the line of cause and effect. Chen Xuan met new partners at Taixu Academy, but was involved in the conspiracy of A Gu, an undercover member of the Bloodscale clan. At a critical moment of life and death, he used the karma plunder to reveal A Gu's true face, showing his wisdom and courage. Chen Xuan was selected to challenge the Chaos Cause and Effect Problem because of his talent, but fell into the trap of Guixu, and Lu Jiaoxi was contaminated by Chaos. During the battle with Lu Jiaoxi, Wuchang Taoist (the future Chen Xuan) disappeared to protect him, revealing that Chen Xuan shoulders the important task of saving the prehistoric world. Chen Xuan accidentally entered the battlefield and used the knitting technique of cause and effect to rescue the Wu clan soldiers, but was chased by three blue birds. Xuanming Ancestral Witch comes to the rescue, and the fate of the two is intertwined. Chen Xuan learned that Xuan Ming was poisoned by chaos, which required fragments of Pangu's ax and the blood of the twelve ancestral witches to remove it. Chen Xuan went to the Netherworld Blood Sea to look for Houtu Ancestor Witch. He encountered many dangers on the way and joined forces with Houtu to fight against the Ancestor Styx. He discovered that Yuanshi Tianzun was hooked up with the Styx River.
