Actress Rosamund Pike was determined to embody fearless correspondent Marie Colvin on screen and to show ‘a woman in all her complexities,’ writes Georgia Humphreys

Christopher Nolan’s Dunkirk (12A) is an epic tale of the greatest mass rescue of World War II, when 400,000 men of the British Expeditionary Force were left stranded and undefended on Dunkirk beach as the German army closed in for the kill.