High Quality Content by WIKIPEDIA articles! Colonel Valentine Vivian CMG DSO MVO, (1886 - 1969), was the first head of MI6's counter-espionage unit, Section V. In the mid-1920s, agency director Sir Hugh Sinclair, the second "C", wanted to absorb MI5, the UK's counter-intelligence agency, into the SIS; when his attempt was finally rejected, in 1925, he formed the CE section, later (1939) renamed "Section V". Between 1925 and 1931, organisational rivalries proliferated among Vivian's CE section, the domestic intelligence agency, MI5, and Scotland Yard. A network of domestic agents known as the 'Casuals' had provided information to CE section. In 1930, after a series of meetings of the Special Services Committee, the Casuals were transferred to MI5, where they became "M Section"; many still provided the SIS with information.