ISBN: 0006138403 - London: Fontana, 1975
"The story concerns a visit made by the President of the Commonwealth nation of Ng'omwana, known as "Boomer" to his friends, to London. He insists on dealing with the London police through Alleyn, an old public school friend of his, rather than allowing Special Branch to work directly with him on his security. Special Branch is not happy at his unwillingness to co-operate with their wishes, particularly as the Boomer had survived an assassination attempt only a few months previously. And then the Ng'omwanan ambassador in London is killed at a reception early in the visit, apparently in mistake for the president."
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