Christopher Nolan is one of the most popular filmmakers working today. He is responsible for some of the most epic films in recent memory as well as many fans' favorite cinematic iteration of Batman. His next film Tenet looks to be another ambitious effort, but perhaps his best movie remains his most underrated.

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Insomnia was Nolan's first studio movie and tells the story of a murder investigation in a small Alaskan town. The film feels very different to Nolan's other films but maintains his signature touches to make it a brilliant thriller. Here are some of the reasons Insomnia is Christopher Nolan's best movie.

Small Town Murder

Insomnia benefits greatly from its well-worn small-town murder genre. Two Los Angeles cops arrive in an Alaskan fishing town to investigate the brutal murder of local teen Kay Connell. The town in question adds so much to the eerie story.

The fictional town of Nightmute in this film is the kind of place where everyone knows each other. As one character explains, there are two kinds of people that live there, those who were born there and those trying to escape something. It makes for an isolated and dreamlike setting.

Al Pacino

By 2002, Al Pacino wasn't starring in as many critically acclaimed films as he was used to before. Some criticized him for leaning into the over-the-top performances in some films while phoning it in with others.

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Without a doubt, his performance in Insomnia stands alongside some of his best. His detective character of Will Dormer is not an easy character to have as a protagonist, but Pacino makes him so compelling and is so effective in Dormer's downward spiral that the audience cannot look away.

Flawed Hero

It becomes clear very quickly that Dormer is an excellent detective. But the movie introduces an interesting subplot involving Dormer and his partner Hap being investigated by internal affairs back in Los Angeles. This is the first hint that Dormer may not be the upstanding cop he seems to be.

The plot thickens when Dormer accidentally shoots and kills Hap then covers it up. Suddenly, the hero cop is made a lot more complicated and the film becomes so much more interesting than the average murder mystery.

The Mentor Relationship

Once Dormer arrives in Nightmute, he meets local cop Ellie Burr (Hilary Swank) who happens to be a big fan of his. Ellie also proves to be a promising detective herself and relishes the opportunity to learn as much from Dormer as possible.

An interesting thing begins to develop between them as Dormer becomes more and more haunted by the murder of Hap. Dormer tries to steer Ellie down a different path and encourages her to be a good cop who goes by the book and doesn't cut corners. He seems to see this as redemption for himself.

Grounded

Nolan makes films unlike any other filmmaker working today. He tells massive and ambitious stories on such a grand scale. From Inception to Interstellar to Tenet, his films just seem to be getting bigger.

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While there is an undeniable fun to those big movies, it's interesting to see Nolan work on a much smaller scale here. The impact of the film is not lessened at all by being a quieter and more intimate story. It would be interesting to see Nolan return to this kind of filmmaking.

Chase Scenes

christopher nolan

While most of the movie is a quiet and tense thriller, Nolan gets to show off some of his impressive directorial skills in the film's pair of excellent chase sequences.

The first chase finds the cops closing in on the killer only to be led into a cloud of fog. It makes for a terrifying and suspenseful sequence. The second chase finds Dormer chasing the killer across a river of logs. Each step is a risk and has the audience holding their breath the entire time.

Dual Investigations

Al Pacino and Hilary Swank in Insomnia Cropped

After the death of Hap which Dormer blames on Kay Connell's killer, the movie becomes divided into two separate investigations. As Dormer continues to look into the death of Kay, Ellie is assigned to investigate the shooting of Hap.

It's a unique framing for the movie as the central detective character is trying to close in on the killer, Ellie is beginning to close in on him. It adds so much more tension to the film, and it is only complicated further when Dormer is contacted by Kay's killer.

Robin Williams

Robin Williams looking sideways in Insomnia

Though he doesn't appear until over an hour into the movie, Robin Williams immediately adds a chilling new energy to the film. He plays Walter Finch, a local author responsible for killing Kay.

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Williams doesn't often play the villain, but this movie shows how effective he is in such a role. He is so unsettling in his polite demeanor and the way he truly seems to think he and Dormer are connected through their murders. It remains one of Williams' best performances.

The Exhaustion

With all the intrigue already in the film, another brilliant detail is added to the story with Dormer's insomnia. He arrives in Nightmute and discovers it is currently in a seasonal cycle in which the sun doesn't go down.

The constant sunlight mixed with his own guilt causes him to go days on end without sleep. Dormer begins to fade into exhaustion and the movie makes the audience feel the same way as you'll leave the movie feeling like you need a good night's sleep.

Daylight

Robin Williams and Al Pacino in Insomnia

The daylight aspect of the movie also separates Insomnia from other films in the genre in an interesting way. While most thrillers are largely set at night and elicit fear from the unknown of the darkness, this movie uses light in a way that is just as effective.

Dormer cannot escape the light which keeps him up and keeps his conscience in constant turmoil. Everything is exposed in the daylight and Dormer is exposed as well, just waiting for his mistakes to come into the light.