When Margaret Thatcher unexpectedly emerged to challenge Edward Heath for the Conservative leadership in 1975, the public knew her only as an archetypal Home Counties Tory Lady, more famous for her hats than for any outstanding talent: she had a rich businessman husband, sent her children to the most expensive private schools, owned houses in Kent and Chelsea, and sat in Parliament representing Finchley. As education Secretary she had made the headlines by cutting the provision of free school milk; but she had voiced no criticism of the policies which led to Heath's defeat. No one for a moment imagined that she would be Heath's successor, nor that she would become one of the most dominant Prime Ministers of the century. Yet almost overnight she reinvented herself. Journalists who set out to discover where she came from were amazed to find that she had grown up above a grocer's shop in Grantham. Within weeks of her becoming Tory leader, an entirely new image was in place, based around the now famous corner shop beside the Great North Road; the strict Methodist upbringing; and her father, the stern but saintly Alderman Roberts who taught her the 'Victorian values' - thrift, temperance, self-reliance, patriotism, and duty - which were the foundations of her future career. It is all true, so far as it goes; yet it is not the whole truth. Following her escape from Grantham to wartime Oxford, through her brief experience as a research chemist in Essex and her first political campaigns as a young Tory candidate in the safe Labour seat of Dartford in 1950 and 1951, to her marriage to Dennis Thatcher, her struggles as a young mother in the 1950s to win a seat in Parliament and her first steps as a junior minister in the early 1960s, he portrays an ambitious and determined woman ruthlessly distancing herself from her roots - until the moment in 1975 when they suddenly became a political asset.