Perhaps the most intellectually titillating films of 2016, Arrival posed audiences with many questions about the nature of existence and humanity’s relation to time. Starring Amy Adams and Jeremy Renner, this film was acclaimed by critics and audiences alike.

Throughout the movie, there are many seeds planted that hint at the overall meaning. Although some of these details are evident to most audiences upon a second viewing, many are not. Here are the top ten details everyone missed in Arrival.

10. White Walls

The character of Louise, played by Amy Adams, finds herself in several different environments over the course of the film. These included her house, classroom, and of course the alien chamber. What audiences aren’t aware of is that these three environments are not necessarily shown in linear time, and they also are tied together with a specific visual cue.

Each of those three sets has a distinct white wall representation. In her house, there is a large window. In the classroom, she has a whiteboard. Finally, the chamber is shown with a giant glass wall separating the humans from the white smoke and alien creatures.

9. The Aliens Never Land

Based on the short story called “Story of Your Life” by Ted Chiang, Arrival has several key differences from its inspiration. One of these is that the alien spacecraft never actually lands on Earth.

Instead, the ships hover over the Earth’s surface. The filmmakers believed that having the film hover above would send a deeper message. In this case, humans would have to take the first step towards interspecies communication.

8. Who’s on First?

As the American scientists grow more comfortable with the heptapods, they eventually give the aliens names. The names chosen are Abbott and Costello, which actually serves as a hint to the overall plot of the film.

A comedic duo from the ’40s and ’50s, the bit Abbott and Costello are perhaps best known for was called “Who’s On First?”. The famous comedy bit all revolves around miscommunication. Multiple words have different meanings, causing the characters involved to hilariously misunderstand one another. That’s essentially what Arrival is all about.

7. Abbott Knows He’s Going to Die

Beings existing outside human conception of time, the heptapods are simultaneously experiencing the past, present, and future all at once. This means that both Abbott and Costello are aware of all the events of the future, including Abbott’s untimely demise.

The two heptapods knew the bomb rogue soldiers had planted on the aircraft. Just before it explodes, Abbott is late to a meeting with the humans for the first time. Halfway through this conversation, Costello quickly floats away, knowing that the bomb will go off. Perhaps Abbott is late because he’s preparing for his own death.

6. No Communication

While the military tries to make sense of the alien species early on in the movie, there are a few throwaway observations made that reveal quite a lot. One such observation made by the military is that the aliens are not communicating with one another.

After learning the nature of the aliens, it becomes apparent why this is the case. The heptapods don’t need to communicate with each other. Each one of them knows exactly what’s going to happen and exactly what each individual needs to do.

5. Language is the First Weapon

When Ian Donnelly, played by Jeremy Renner, first enters the film, one of the first things he says is, “language is the first weapon drawn in a conflict.” Anyone who has already seen Arrival from start to finish knows this one statement foreshadows the entire film.

The biggest conflict of the movie is the confusion between the heptapods’ word for language/weapon. Humanity’s unableness to make a distinction between the two nearly starts a massive world-ending conflict.

4. Circle of Fifths

In music, there is a concept called the “circle of fifths.” Essentially, there is an interval known as a perfect fifth. If you string multiple of these fifths together, it gives you a sort of circular melody that plays like a musical wheel.

Arrival’s musical theme is written in a circle of fifths. Circles are a big theme in the movie, all of which lead to the idea that while we view time linearly, it is actually circular in nature. Having this theme play into the music itself is a wonderful hidden detail.

3. There is No Time

Towards the end of the film, the heptapods send Russia a message that almost causes them to start a massive war. That message was “there is no time, use weapon.” While Russia takes this as a threat of battle, the aliens were quite clearly sending a different message.

Based on the aliens’ nature percieving time all at once, “there is no time” clearly meant the linear construction of time you have is not accurate. Also, the “weapon” actually meant the language they were trying to give to humans.

2. The Heptapods Know Everything

Arrival is centered around Louise and Ian trying to teach the aliens how to speak English and learning the heptapod language. What becomes clear after repeat viewings is that Abbott and Costello already know everything. With time being viewed all at once to these creatures, they must already know everything Louise and Ian are about to show them, meaning they understand the two humans perfectly.

Knowing that fact changes the context of many of the meetings between the human scientists and the heptapods. While Renner and Adam’s characters think they are teaching the heptapods, it is really just the heptapods that are teaching them.

1. 4-Dimensional Beings

At the end of the movie, it appears that all of the alien ships merely vanish out of thin air. This confuses many of the humans in the movie. There is, however, a simple and clear explanation as to how this could have happened.

This alien race is made up of four-dimensional beings that perceive time as another dimension. Because of this, it is likely that they can move in and out of time at free will. Being three-dimensionally beings, we are unable to perceive this movement. Therefore, it appears to humanity that the heptapod’s spacecraft merely vanished in thin air.