I have, as per an ancient challenge, written this story. It's one thing to write such a story; it's another thing to tell it in front of people hoping to be entertained, and I will do the other thing on Thursday.
On the upside, how can I never have heard of the Dreadnought Hoax before yesterday? The Bloomsberries blacked themselves up, pretended to be a delegation of Abyssinian royals and got a guided tour of the pride of His Majesty's fleet. They signalled their appreciation with wondering cries of 'Bunga! Bunga!', which small children repeated in a spirit of urchinish irony to the real Emperor some years later.*
My favourite line from the Wikipedia page is: 'When they were on the train, Anthony Buxton sneezed and blew off his false whiskers, but managed to stick them back before anyone noticed.'
* When HMS Dreadnought rammed and sank a German U Boat during the Great War, one of the congratulatory telegrams read, 'BUNGA BUNGA'.