Fosca to powieść włoska Iginio Ugo Tarchetti z 1869 roku, początkowo wydana w formie seryjnej. Fosca posłużyła za podstawę filmu Passione d'amore Ettore Scoli z 1981 roku, a także musicalu Pasja Stephena Sondheima z 1994 roku.
After a passionate but ill-fated love affair with the beautiful married woman Clara, the young army officer Giorgio is transferred from Milan to Parma, where he meets the sickly and unattractive Fosca, the cousin of his commander. Although initially repelled by her, he becomes fascinated by her and slowly succumbs to her morbid, manipulative charms. A witty and satirical critique of romance, desire, and bourgeois sexual conventions, Tarchetti's sophisticated and controversial novel is a masterpiece of 19th-century Italian decadent literature.
After a passionate but ill-fated love affair with the beautiful married woman Clara, the young army officer Giorgio is transferred from Milan to Parma, where he meets the sickly and unattractive Fosca, the cousin of his commander. Although initially repelled by her, he becomes fascinated by her and slowly succumbs to her morbid, manipulative charms. A witty and satirical critique of romance, desire, and bourgeois sexual conventions, Tarchetti's sophisticated and controversial novel is a masterpiece of 19th-century Italian decadent literature.