"Never Judge a Lady by Her Cover" is a historical romance novel by Sarah MacLean, set in the Regency era. The story centers around Lady Georgiana, who has meticulously crafted her reputation as a scandalous figure in society, despite her true character being quite the opposite. She is driven by the desire to maintain her family's legacy and protect her secrets, which leads her to lead a double life. The plot thickens when the charming and formidable the Duke of Ainsley becomes involved in her life. He is intrigued by her dual nature and determined to uncover the truth about her. Their interactions are filled with tension and undeniable chemistry, highlighting the complexities of love and societal expectations during that time.