The SS would move in under SS Colonel Dr Franz Six, former head of the faculty of economics in the University of Berlin, and one of Heydrich's most able security agents. His headquarters would be in London, his responsibility to put the SS Action Groups into service behind the advancing German army; their headquarters were planned to be in London, Bristol, Birmingham, Liverpool, Manchester, and Edinburgh.
It is well-known that many prominent politicians, thinkers, and writers hostile to the Nazis were on the list of over 2,000 people to be arrested immediately. Headed by Churchill, they included H.G. Wells, Noel Coward, Rebecca West, Bertrand Russell, J.B. Piestly, and C.P. Snow. It seems that Britain, the despair of Hitler, would have become a second Poland: the Battle of Britain saved the island people from a dreadful fate.
(From History of the Second World War)