Dreams in the Mist

The heroine Mo Luquan accidentally fell from a building and died, but she went back to the beginning. She had been dreaming about her falling from a building on a rainy night. She didn't know whether this was her lost memory or the process she witnessed with her own eyes. The heroine's twin sister hates the heroine because her family hates her? Or is there another reason? Is this related to the rooftop jumping case? The female protagonist skips to the senior year of high school and meets the male protagonist. The male protagonist Ge Qiuming inspires to become a trace examiner. Later, he investigates the falling case step by step. They fall into a cycle of memories and lose their memory while investigating step by step. The twin sisters have the same crescent birthmark, and so does the deceased. Who is the deceased?