A former NHS nurse has been brought in to bring order and discipline to the chaos of Boris Johnson’s faltering Downing Street machine. Samantha Jones, 50, became No 10’s first chief operating officer in February as part of the prime minister’s revamp of his team. Just how powerful her role would be emerged this week. The existing No 10 operation, alongside teams in the Cabinet Office supporting Johnson and his top table of ministers, will be in a group led by her. Her rank of permanent secretary is the second most senior official at the centre of government under the cabinet secretary, Simon Case. But amid whispers that Case has been damaged by the Partygate revelations – many civil servants under him were fined and he was present at more than one of the events investigated by Scotland Yard – she seems to have been handed a large chunk of the cabinet secretary’s former responsibilities. It is a rare and steep rise in Whitehall to the very top of the civil service for someone outside the usual route followed by mandarins. Most of her colleagues of similar rank will have been fast-tracked through Oxbridge and the senior ranks of major government departments. Jones worked her way through the NHS to become the chief executive of two hospital trusts. She has been working in Downing Street since last April. She was appointed as the prime minister’s top adviser on NHS transformation and social care. She began her career as a nurse at Great Ormond Street children’s hospital in London but rapidly moved into management, taking part in the NHS’s two-year graduate management training scheme. In an interview, she said: “I said, ‘I don’t know why I want to be a manager but I’ve got four brothers. I’m too stroppy. I have to stand by my beds while the consultant does his ward round and I’m not allowed to speak until I’m spoken to — and I’m not having any of that.’ ” Jones became the chief executive of Epsom and St Helier NHS trust and later the West Hertfordshire hospitals NHS trust, and was one of the youngest chief executives in England. She also worked as a director of care strategies at NHS England. She entered Downing Street after working in the private sector. She became CEO in the UK of Centene, part of a US private health group, which recently became one of the largest primary care providers in England, with 58 practices and more than 500,000 patients. Her subsequent re-entry into the public sector led some to believe she was being lined up for last year’s vacant CEO position of NHS England but in the end the job went to another high NHS flyer, Amanda Pritchard. Whitehall insiders hope her management skills will be useful in assessing whether the structure of Downing Street is as effective as it should be. A mother of twins, she once said her favourite books include Machiavelli’s The Prince, while her dream dinner party guests would include Hillary Clinton, Barack Obama, David Walliams and Nelson Mandela.