Christopher Nolan has become one of the most exciting filmmakers of our time thanks to his ambitious and epic movies. While his Dark Knight trilogy and films like Inception have been huge genre successes, perhaps his most ambitious film to date was his war film Dunkirk.

RELATED: Christopher Nolan's 10 Best Movies, According To IMDb

This is the harrowing true story about the World War II rescue mission of thousands of British soldiers from the beaches of Dunkirk. Nolan's considerable skills as a filmmaker helped to tell this intense and powerful story filled with unforgettable moments and things that are easy to miss on the first viewing. Here are some hidden details in Dunkirk that everyone missed.

Timelines

Nolan's storytelling with Dunkirk was as ambitious as his filmmaking. He sought to tell the story from different perspectives, each occurring in their own time. The jumping between timelines caused confusion for some viewers, who might have failed to notice a small detail at the beginning of the film.

The film opens by introducing those three main timelines set on the beach, the sea, and the air respectively. However, some viewers might have missed the title cards that explain how long each timeline covers. The beach section covers one week, the sea covers one day, and the air covers one hour.

The Crossing

George holding some life jackets in Dunkirk

One of the most frustrating and effective aspects of the film is that the British forces are so close to home yet cannot quite reach it. Looking across the beaches of Dunkirk, England is almost visible, and indeed, the small vessels are able to make the crossing in one day.

RELATED: 10 Of Christopher Nolan's Favorite Films, Ranked

Nolan took it upon himself to better understand what that crossing was like. Before filming, he, his wife, and some friends made the crossing themselves much like all the civilian vessels did in the film.

Unknown Actors

The film is filled with several notable actors like Tom Hardy, Mark Rylance, and Cillian Murphy, yet their roles are more of a supporting capacity. The main focus of the film is the character of Tommy and his fellow soldiers who are stuck on the beach.

These roles are played by young unknown actors. Part of the reason behind this is that the soldiers on the beach at Dunkirk were mostly inexperienced young soldiers. Having actors the audience didn't know sells that inexperience. Ironically, Harry Styles, perhaps the most famous person in the cast, plays one of these soldiers as Nolan had no idea who he was when he cast him.

Michael Caine

Michael Caine in Tenet trailer

Michael Caine has become something of a good luck charm for Nolan over the years. Ever since collaborating for the first time on Batman Begins, Nolan has cast Caine in every single one of his films, including his upcoming Tenet. However, fans might have missed Caine's role in Dunkirk.

Unlike their other films together, Dunkirk is their first collaboration in which Caine does not appear on the screen. He is only heard, serving as the voice of Tom Hardy's commanding officer who is shot down early in the film and never actually seen.

The Score

Fionn Whitehead running through the streets in Dunkirk

Another important collaborator of Nolan's has been composer Hans Zimmer. The two have worked together multiple times, with Zimmer's iconic scores for Nolan's works ranking among his best while also being very important aspects of each of these films.

RELATED: Hans Zimmer's 10 Most Iconic Soundtracks, Ranked

For Dunkirk, the two came up with a very distinct idea for the score. The music was meant to be a building threat, such as the one that faced the soldiers on the beach. Listen closely to the score and the ticking of a watch can be heard. In fact, this ticking sound was provided by Nolan's own pocket watch.

Civilian Ships

Dunkirk Sinking Ship

Part of what makes the incredible true story so moving is how the rescue of these soldiers came down to the people of England. Civilian boats were used to sail to Dunkirk when military vessels proved unsuccessful. The scene of the civilian ships appearing on the horizon is a truly powerful moment.

While there are many boats seen in this shot, some of them are of special note. Twelve of the boats seen in the rescue sequence were the actual ships that participated in the real-life rescue all those years ago.

The Unseen Enemy

The teaser trailer for Dunkirk

Dunkirk is a very different kind of war movie than mainstream audiences are used to seeing. This is not a story of the battles of WWII, but rather just the survival of soldiers who have been defeated. The film takes some unique steps to communicate this story which further differentiates it from other war films.

One of the most notable differences is that no enemy soldiers are made clearly visible at any time in the film. Be it the enemy pilots in the skies, those firing at the soldiers on the beach, and even the ones who take Tom Hardy captive at the end, they are all either out of focus or totally unseen.

Air Support

Dunkirk provides a glimpse at the heroism of the air force pilots who were sent to protect those on the beaches. However, the film also makes the point of showing those on the beach cursing the air force for their lack of help.

RELATED: 10 Effects From Christopher Nolan Movies You Won't Believe Weren't CGI

It's possible that the soldiers on the beach would have been unaware of the air force's activities at the time. While some did fly over to protect the beaches from bombers, most of the fighter pilots were fighting further inland, preventing more enemy planes from ever reaching the beach.

Charles Lightoller

Mr. Dawson and the Shivering Soldier in Dunkirk

While all the characters in the film are fictional, some are based on real individuals. One of the most interesting figures is Charles Lightoller, the man who served as the basis for Mark Rylance's character.

Lightoller was a member of the British Navy who fought in World War I. Following the war, he took a job as an officer for the White Star Line shipping company and served on the Titanic. He faced controversy for allowing several lifeboats to leave without being at full capacity. Following the sinking, he retired and started a private yacht company. During the Dunkirk evacuation, he sailed his personal vessel over and helped save over a hundred soldiers.

Landing The Spitfire

Tom Hardy in Dunkirk

Nolan impressively was able to use a lot of real aspects of the war in his film, including the spitfire planes that Tom Hardy's character flies in the film. This included the sequence at the end of the film where Hardy's character, having used up all his fuel, lands on the beach.

This stunt was performed by the real owner of the plane on camera. However, they soon found the plane was stuck in the sand and there was a rush to free the priceless plane before came in.

NEXT: Tom Hardy's 10 Best Movies, According To Rotten Tomatoes