Steed is assigned to prevent the assassination of King Tenuphon after one attempt fails. Major Harrington is already arranging a second try - the King will die from a sniper's bullet as he walks on his balcony. Steed does check for this eventuality, but the owner of the house opposite, Mrs Carter, does not arouse his suspicions. Steed's sixth-sense ensures that the King remains safe and the royal bodyguard disposes of Harrington.
Unity Bevis (Unity Bevis-Jones) may be familiar to readers who saw the "Christian the Lion" videos on YouTube - she was a friend of the Australians who owned him and was a frequent visitor to their flat and shop.