After a stellar career in the Secret Intelligence Service (SIS), better known as MI6, an unassuming man with a passion for bridge and a taste for malt whisky was in line to become head of that service, or ‘C’. The year was 1990. Roger Horrell was the favoured candidate to assume control of Britain’s foreign intelligence service.

Roger had been a friend since we met in Africa some 20 years earlier. I knew him as an MI6 officer but had no idea that he was destined to become Britain’s master spy. Looking back at our regular club dinners in London, he may have hinted at his likely promotion but that is easy to say now. As befits his calling, Roger was a very secret man.

Behind his stories about life in the Kenyan bush, there was someone else – a more private person

I did however know that my friend had been recognised as an MI6 highflier since the success of the Lancaster House conference on Rhodesia in 1980 to which he made a major contribution. What I did not know, and neither did anyone in MI6, was that Roger’s swift rise was to lead to disgrace and departure from a world he had served so well.

There was no hint of that sad finale to a brilliant career when Sir Colin McColl, head of MI6, named three candidates to replace him on his retirement. Roger was recognised within the service as the favourite. The final choice rested with Sir Percy Craddock, foreign affairs adviser to the prime minister, Margaret Thatcher.

Craddock turned all three down, airily explaining that none had a ‘Whitehall profile’ and that he had not heard of any one of them. To general surprise and some irritation, McColl continued as ‘C’ for two more years.

Roger shared the general frustration. He cloaked his feelings with the graveyard discretion common to all in the service. He was now close to the retirement age of 55. He would only have continued in the SIS had he been appointed to head it.

His career had been shaped by two years working largely on his own as a district officer in the colonial service in Kenya. This was the 1950s, when large swaths of the country were only loosely controlled from Nairobi. Kenya’s independence in 1963 ended the posting. MI6, which had noted Roger’s grasp of local African politics and his impressive record governing remote areas of the country entirely on his own, recruited him.

Roger’s first posting under diplomatic cover was to Dubai, then administered by Britain. It was a chaotic and violent time in the Middle East and something of a baptism of fire for the 26-year-old new recruit to the shadowy world of espionage.

Roger proved himself well able to deal with the complex and often contradictory politics of a region fired up by President Nasser’s calls for revolution. He did not, however, speak Arabic and was grateful to be sent next to Africa, his first and last love.

Based initially in the Ugandan capital of Kampala, Roger was posted to Lusaka in Zambia in 1976. There he quickly learned that rival black nationalist groups were more adept at fighting each other than in taking the battle to Ian Smith’s white regime in neighbouring Rhodesia.

As the declared MI6 head of station in the Zambian capital, Roger had to overcome initial suspicion and sometimes the outright hostility of the various nationalist groups. Britain was........

© The Spectator