This first full-length trailer for Christopher Nolan’s dark and gritty World War II film “Dunkirk” has hit the web.

Featuring the major film debut of One Direction member Harry Styles, “Dunkirk” is Nolan’s look at the epic “Operation Dynamo” during the battle of Dunkirk. The movie depicts the real life events which saw soldiers from Canada, Great Britain, France and Belgium embroiled in a harrowing mass evacuation of over 300,000 troops after a rapid invasion of northern France by Hitler’s German forces.

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Styles is in good company for the sombre war drama. He’s joined on screen by an ensemble cast that includes Tom Hardy and Cillian Murphy as terrified troops, as well as Kenneth Branagh and recent Oscar-winner Mark Rylance.

“Dunkirk” will open in theatres on July 21.