"Madame X" is a famous portrait painted by John Singer Sargent in 1884. The painting depicts a woman in a black gown, with a striking pose and a mysterious expression. It was originally commissioned by Virginie Amélie Avegno, a socialite, and is known for its bold use of color and dramatic lighting. The artwork caused a scandal when first exhibited due to the subject's provocative pose and the revealing nature of her dress. Today, "Madame X" is considered a masterpiece of American art and is housed in the Metropolitan Museum of Art in New York City.