From 1962 to 1966 David Cooper ran an experimental hospital ward in Villa 21 of Shenley Hospital, Hertfordshire, England. In the histories of mid-twentieth-century psychiatry and anti-psychiatry, this ward has been almost entirely forgotten, overshadowed by the figure of R.D. Laing and his Kingsley Hall experiment. This study attempts to construct a history of Villa 21 and to reassert its historical importance as a manifestation of British anti-psychiatry and the radically anti-institutional politics of its time. Beginning before the opening of the ward, this article follows the story of Villa 21 on theoretical, practical and personal levels through its experimental journey and into its dramatic aftermath when Cooper's experiment was ideologically obliterated by his successor Michael Conran and physically obliterated by the Hospital administration. It contends that Villa 21 is an example of anti-psychiatry's attempt to engage with the very structure of society at a profound level.