Romance of a Twin Flower (春闺梦里人) is adapted from the novel written by Bai Lu Cheng Shuang. In the original novel, our female is a modern working woman who finds herself as one of the villains in the book she’s reading: abandoned-main-wife-turned-evil of a domineering marquis. In the drama, they changed that part and made her a twin who loses her memory and replaces her twin sister in the manor with the same marquis. She has exceptional business skills and resolves many crisis for the family, earning the love of the arrogant man of the house eventually.
You can read the translated novel at Fuyu Neko’s website.