Lady Caroline's most famous work is "Glenarvon", a Gothic novel that was released in 1816 just weeks after Byron's departure from England. Although published anonymously, Lady Caroline's authorship was an open secret. It featured a thinly disguised pen-picture of herself and her former lover, who was painted as a war hero who turns traitor against . The book was notable for featuring the first version of the Byronic hero outside of Byron's own work as well as a detailed scrutiny of the Romantic Period and, more specifically, the Ton. Lady Caroline included scathing caricatures of several of those prominent society members. One of them, the Countess of Jersey, cancelled Lady Caroline's vouchers to Almack's in retribution for her characterisations. This was the opening salvo in a backlash that found Lady Caroline blackballed from fashionable society: although her sister-in-law, Emily Lamb, Countess Cowper, got Lady Caroline readmitted to Almack's in 1819, her reputation never fully recovered.