In Netflix’s glossy royal drama The Crown, the Queen and Prince Philip rub shoulders with some of the 20th century’s most famous faces, from Winston Churchill to John F Kennedy.

But one episode in the new second series shines a light on a less well-known figure: John Grigg, 2nd Baron Altrincham. His name may be unfamiliar to many now, but for a few months in 1957 he was one of the most famous – and most hated – men in Britain.

He was attacked in the street, denounced in the press, and once received an envelope of human excrement through his letterbox, stamped “On Her Majesty’s Service”. An angry Italian knight even challenged him to a duel (more on which later).