Senior MI6 spy Kate Henderson is running an operation in Istanbul when she overhears her Russian targets discussing an asset who is now senior in British politics and set to be in 'pole position' when the Prime Minister resigns.

Unable to act on the information without jeopardizing UK democracy, Kate and MI6 sit tight. But when the Prime Minister reveals he is resigning, Kate begins investigating those senior in politics closest to her - her best friend, the current Chancellor and her husband, her chief aid. Can Kate and MI6 find out the asset without destroying British democracy in the process?