Factual error: The Black Watch sergeant major wears a crown over three chevrons, which was the correct rank badge for a company sergeant major until 1915. However, this is at least 1916 (as conscription has started and the men are wearing steel helmets, both introduced in 1916). CSMs had been redesignated as warrant officers in 1915 and now wore a crown on the lower sleeves instead.
The King's Man (2021)
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Directed by: Matthew Vaughn
Starring: Ralph Fiennes, Gemma Arterton, Harris Dickinson
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Duke of Oxford: I know you want to fight, but there are other ways of doing your duty.
Trivia: There is an extra scene with Adolf Hitler, Lenin, and the Shepherd's assistant that comes on after the credits roll.