Joseph Mallord William Turner (1775-1851) was both the most admired and the most derided painter of his time. His ambition was to excel in all forms of painting and he worked with every possible painterly medium. His vision soon outran the taste of his contemporaries, as he began to experiment in pure forms of light and colour, producing masterpieces of impassioned tonality that were still unsold as the time of his death. Through he travelled widely, he never strayed far from the banks of his home river. He lived by the Thames, in cottages in Hammersmith and Isleworth, and he died by it, in a rented house in Chelsea. He was secretive and kept a mistress about whom little was known. Reputed to be taciturn, miserly, even mad, he was, in truth, a generous en emotional man who grew tired of the world' attention. Peter Ackroyd's brilliant short biography reveals the genius of the artist and the abiding qualities of the man. In the process, it describes Turner's London and the singular characteristics of a "Cockney visionary" who changed the nature of English art.