Painted by John Singer Sargent and admired by Sarah Bernhardt, Isabella Stewart Gardner was both popular and unconventional. A passionate art collector and philanthropist, she surrounded herself with artists, writers and musicians, who constituted her court in both Boston in Venice. Written between 1879 and 1914, James's letters to her - whom he once described as "a locomotive - with a Pullman car attached" - vary greatly in their subject-matter and tone: by turns affectionate, ironic, gossipy and philosophical, they give us a fresh insight into a man who to this day remains in many ways a mystery.