Interstellar explained

What is Interstellar about?

Interstellar’s primary theme has to do with logic versus emotion. The dynamic permeates almost every part of the film. For example, the school system has turned away from teaching kids to dream and instead grounded itself to what is the most practical and necessary. Most of the pivot points in the plot come down to characters acting out of logic, fear, or love. While Nolan does celebrate science and engineering, he doesn’t shy away from aggrandizing and lionizing the need for the emotional component. This is most obvious in his repeated references to Dylan Thomas’s legendary poem “Do not go gentle into that good night”, with special emphasis on the final line, “Rage, rage against the dying of the light.” That ties-in to the idea of the survival instinct that can motivate someone to act beyond what logic is otherwise telling them.   

Cast

• Joseph Cooper – Matthew McConaughey
• Young Murph – Mackenzie Foy
• Murph – Jessica Chastain
• Elderly Murph – Ellen Burstyn
• Young Tom – Timothée Chalamet
• Tom – Casey Affleck
• Donald – John Lithgow
• Dr. Amelia Brand – Anne Hathaway
• Professor John Brand – Michael Caine
• Romilly – David Gyasi
• Doyle – Wes Bentley
• TARS – Bill Irwin
• CASE – Josh Stewart
• Mann – Matt Damon
• Written by – Jonathan Nolan | Christopher Nolan
• Directed by – Christopher Nolan

The ending of Interstellar explained

Recap

The ending of Interstellar begins when Coop descends into the black hole Gargantua. As his ship is destroyed and his doom seems inevitable, he ejects, only to wind up in the fifth-dimensional space of a tesseract. Surprisingly, the tesseract gives him access to Murph’s bedroom, at any point in space-time. Coop uses this ability, initially, to lament his fate, signaling “Stay” in Morse code as he watches the moment where he said goodbye to his daughter before embarking on this very mission. Once he understands what this means, though, and that TARS has the quantum data about Gargantua, Coop manages to code the information into the second hand of the watch he had given Murph so father and daughter could feel connected. 

Murph, in the room, on the brink of epiphany, finally puts all of her memories together to realize that her ghost was her father. That he had kept his promise and returned, and been there, in this alternative form, for her entire life. Grabbing the watch, she recognizes the twitching of the second hand as Morse. Back at NASA, she translates the information, unlocks the data, then manages to save humanity by solving the gravity equation that will allow the population to leave Earth. 

Coop is finally aware that the alien superbeings inexplicably helping humanity are just humans in the future ensuring their own survival. The tesseract, having served its purpose, collapses, flinging Coop back through space-time, past his own self, making him the “alien” Amelia shook hands with in the wormhole. He arrives in the space outside Saturn, where he’s retrieved by Murph’s interstellar ark (Cooper Station). 

After two weeks, Coop has a brief reunion with Murph, who, old as she is, only has a little bit left to live. She tells her father that no parent should watch their child die, that she has her own family to be with, that he should do what he does best—explore. That means going after Brand and beginning the preparations for when humanity reaches the planet Brand’s preparing for colonization.

The final scene is of Brand, having buried Edmunds, looking off at the beginnings of the new colony of America. 

Meaning

Thematically speaking

Interstellar’s primary theme has to do with the often contentious relationship between logic and emotion. How they tend to be the opposites of one another. Someone acting out of logic might lack emotion. Someone acting out of emotion might lack logic. Most of the movie leading up to the final sequence had shown society and characters at each extreme. Or at least leaning one way over the other. Like when Coop leaves for the mission, Murph reacts purely out of emotion. Or when Tom makes the video saying he has to let his father go, it’s a logical choice. Then there’s the scene where Coop and Brand argue about which planet to explore after Miller’s. Brand wants to head to Edmunds because she loves him and wants to see him but also because she believes in the data. Coop writes off her point of view as purely indulgent and opts, instead, for the logical choice of going to Mann’s planet because it had the superior data. 

But at the very end, Coop realizes that love can transcend dimensions, just like time and gravity. Ultimately, it’s the combination of his knowledge and education with his love for his children that allows Coop to relay the necessary information to Murph. And it’s Murph’s combination of knowledge and education with her love for her father that allows her to receive the message. We have a synthesis of logic and love that results in humanity overcoming the miserable situation it’s in on Earth. 

Reinforcing all of that is the fact that Brand was right in wanting to go to Edmunds. Of the three potentially habitable planets, his was the only one that actually could sustain life. In reality, we could chalk it up to coincidence. But in a narrative that’s purposefully constructed, it’s confirmation of love’s powerful, extraordinary influence. 

Interstellar’s ending does give us closure on several sub-themes throughout the movie. 

The beginning portion, while Coop’s still on Earth, introduces the idea that humans have become scared of taking risks and spend more time in the dirt than they do the sky, both literally and metaphorically. By the end, humanity is dreaming big again, returning to embodying the ideals of seeking knowledge and adventuring. 

The second quarter explores the individual cost of huge endeavors like this. Coop leaves his kids. Brand never got to have a meaningful relationship with Edmunds. Miller, Mann, and Edmunds all gave their lives to discover potential new worlds. The team loses Doyle. They lose decades. But the sacrifices weren’t in vain. Everyone contributed to the eventual survival of the human species. 

Then the third quarter brings up the idea of survival instinct and the way in which people will, when at the brink, fight back. Regardless of the logic of it all. Mann embodies this in a negative way, in the most selfish way. While Coop and Brand demonstrate the way in which survival often depends on others helping us. That leads right into the emotional component that is the focus of the final sequence. 

Practically speaking

The end of Interstellar is emotionally powerful and cathartic. But it does raise some plot-based questions. Like how did Coop and TARS survive being inside a black hole? How did humans evolve to operate on the fifth-dimension? If they’re that powerful, and have that kind of influence over space-time, why did they need to rely on a father sending a Morse code message to his daughter through a watch after entering a black hole? How did the evacuation of Earth go? What did solving the gravity equation actually do? What happened to Cooper’s son, Tom? 

There is an irony to the movie essentially telling us emotion trumps logic as it concludes with a stretch of story elements that create a number of questions without much in the way of satisfying answers. If you want to give the film the benefit of the doubt, you view this as an example of form meets function, a meta choice that formally reinforces the main theme. If you want to be critical, you might call it a bit of a cop out. Given the popularity and adulation the general movie-going audience has for Interstellar, it seems that Nolan’s thesis has been proven true—love is more powerful than logic.

The themes and meaning of Interstellar

One-dimensional thinking versus multi-dimensional thinking

Coop’s children, Tom and Murph, each embody different ways of being that are at the core of Interstellar. Tom is a one-dimensional thinker who is concerned only with what’s immediate and practical. While Murph is a multi-dimensional thinker who cares about the future. 

In the film’s early sequences, Coop is saddened by the state of human civilization, especially the educational system. Coop feels like Tom has potential to do something more than just be a farmer. But the school says farmers are what society needs, anything more is not only unrealistic but unnecessary. They’ve gone so far as to start teaching that the moon landing was a hoax. Not because they believe it but because it means society will stay focused on the practical, immediate needs rather than “wasting” time and effort on “fruitless” endeavors like space exploration. 

When Coop tries to talk to Tom about this, Tom says he likes farming and is more than okay with having that be his future. Fast forward to the end of the film, and we see that Tom has grown into a simplistic person. He hasn’t changed much about his house or his life. When Getty and Murph tell him that he has to leave the farm because the dust has Tom’s wife and son on the brink of death, Tom refuses to go. That’s how rooted he is in short-term thinking and hanging onto the past. The reason he cites for not leaving? Because his mom, grandpa, and first son are buried in the backyard. He’d sacrifice his entire future just to hang on to his history. 

Murph, on the other hand, is the more daring of the two children. She wants to be more, do more, experience more. She’s a rule-breaker. A fighter. Her spirit is immense. And it’s that way of being and thinking that makes her the person who solves the extinction of humanity by literally communicating across dimensions. 

In this way, Nolan uses Tom and Murphy as a parable about ways of being and thinking. Tom is the negative example, the who not to be. Murph is the positive example, who we should all aspire to. 

At the very end of the movie, a character tells Coop they wrote a paper on him in high school. It’s seemingly a throwaway line that many will chalk up as simply a relaying of Coop’s fame. But it’s really a purposeful callback to the school subplot that opened the movie and shows that the school system post-Murph has gone back to a system that inspires kids to want more and want to be more. 

Learning how to adapt

We discussed how Tom wanted to stay at his house because of his family history. Even though it would mean the demise of his wife, son, and probably himself, due to lung complications from all the dust. That serves as a microcosm for what was happening on Earth. The remaining governments had mostly given up on finding a solution to the problem and were, instead, just biding their time, surviving for as long as possible. It’s a scarcity mindset. A shackling zeitgeist that says that nothing more is attainable, obtainable, or possible.

When Coop and his kids bring down the lost drone from India, Coop expresses how he plans on stripping it down, using its batteries to power equipment, etc. Murph, a bit sad, asks if they can’t just let the drone go. “It wasn’t hurting anybody.”

Coop follows up with, “This thing needs to learn how to adapt.” For her part, Murph quickly understands, demonstrating that multi-dimensional, growth-mindset thinking. Her response? “Like the rest of us.” 

Interstellar serves as a reminder that we can’t become stagnant. That if something isn’t working, we need to adapt. 

Isolation hurts

Throughout the movie, there’s a pretty big dichotomy between characters who are part of a group versus those who are on their own. The three astronauts who went out on Project Lazarus all ended up alone on their individual worlds. None of the three survived. Well, Mann did. But only because Coop’s team arrived. Even then, the time Mann spent isolated ruined him and reduced him to a selfish, desperate creature who was willing to sacrifice everyone else for his own benefit. Compare that to Coop having his crew of Brand, Romilly, Doyle, TARS, and CASE aboard the Endurance. While not everyone on the team survived, they fared much better because they had one another. 

We see this back on Earth, as well. Tom isolates with his family and grows more and more despondent and difficult. Meanwhile, Murph joins NASA and is around a community of people all working together on a dream. She isn’t necessarily happier than Tom, but you could argue her life is far more fulfilling and what she accomplishes is far more meaningful. 

Why is the movie called Interstellar?

Merriam-Webster defines “interstellar” as located, taking place, or traveling among the stars especially of the Milky Way galaxy. On the surface level, the title makes sense—the movie is about a journey through space. An interstellar adventure. The characters literally travel to another galaxy. 

We can get a bit deeper, though. The root of the word is inter- and stella. Latin for between and star. So between stars. This phrasing is a bit more stripped down. It’s broader. And that works with the very end of the movie. Because while a bulk of the story is the journey Cooper and the team go on from one solar system to another, and the pilgrimage humanity will make to its new planet, to make that happen, Coop ends up in a tesseract, a dimensional place that exists between the stars that we can’t, at this point, perceive. 

So there’s something to the title as embodying not just the trek between stars but the travel between dimensions. 

If you want to go even further, we can flip the application of the word “interstellar”. The story is about individuals and a population doing everything they can to survive. That idea of survival, of raging against the dying of the light, comes up over and over again. With this in mind, instead of the title referring to the journey the characters go on through space, it would have a more poetic and existential application as referring to life itself throughout the cosmos doing what it must to survive. What we see with humanity in the movie is just one example of the universal struggle all living things face. “Interstellar” captures the totality of this plight throughout space and time.  

Important motifs in Interstellar

Dylan Thomas’s poem “Do not go gentle into that good night”

Here’s the full poem:

Do not go gentle into that good night,
Old age should burn and rave at close of day;
Rage, rage against the dying of the light

Though wise men at their end know dark is right,
Because their words had forked no lightning they
Do not go gentle into that good night.

Good men, the last wave by, crying how bright
Their frail deeds might have danced in a green bay,
Rage, rage against the dying of the light.

Wild men who caught and sang the sun in flight,
And learn, too late, they grieved it on its way,
Do not go gentle into that good night.

Grave men, near death, who see with blinding sight
Blind eyes could blaze like meteors and be gay,
Rage, rage against the dying of the light. 

And you, my father, there on the sad height,
Curse, bless, me now with your fierce tears, I pray.
Do not go gentle into that good night.
Rage, rage against the dying of the light. 

-Dylan Thomas

There’s a cool dynamic going on where the concluding statements of each stanza— “do not go gentle into that good night” and “rage, rage against the dying of the light” — can serve as both statement and demand. As a statement, it’s the narrator saying that the Good men rage against the dying of the light. As a demand, it’s the narrator speaking to the Good men, reminding them that they should rage.

This duality doesn’t necessarily change the meaning of the poem so much as it affects the tone. 

As a statement that these wise men, good men, wild men, and grave men, all fight for life, each group serves as a role model for the narrator’s father. It’s the narrator essentially pleading for his dad to be like them. Everyone else is fighting, please, do the same. 

As a demand, the overall state of the world is a lot sadder. It’s the narrator looking around and seeing all these groups of people losing their will to survive and calling out to them to do something about it. It moves from the broader state of things to the more intimate and personal as we realize the narrator’s father is also at this point of lost fire. 

In the former, the macro state of the world is fine, it’s just the narrator’s father who isn’t fighting. The latter is a lot bleaker about the broader zeitgeist. Aside from the wise men, everyone else is allowing the night to consume them.

Given what we know about the film’s themes and the statement Nolan’s making about the human spirit and how people need to continue to strive for more, to improve, to dream, to not just fight to survive but fight to thrive—Dylan Thomas’s poem is the heart of the entire film. 

Questions & answers about Interstellar

Is Murphy’s Law relevant?

Since it’s mentioned specifically by characters in the film, it does feel worth discussing. But it’s also a bit odd. The saying is classically that anything that can go wrong, will go wrong. Yet when Murphy brings this up to Cooper, asking him why they named her after something bad, Coop replies that it’s less about what can go wrong and more about what can happen. It’s a much more positive interpretation of the law. You could see how it plays into some of the themes about one-dimensional thinking vs multi-dimensional thinking, as well as learning to adapt as Coop adapts the phrase to something a lot more neutral, even positive. 

It can also serve as a bit of a catch-all for the wild things that happen in the story. If someone asks how Coop could possibly survive in a black hole—Murphy’s law! What can happen, will happen. 

But it doesn’t necessarily feel meaningful enough to include as a main theme or motif. 

Why did the combines drive up to the house?

The magnetism of Coop from the future suddenly being present at the house. Essentially a byproduct of the tesseract. 

What does “Once you’re a parent, you’re the ghost of your children’s future” mean?

We’ve all heard of the concepts of nature and nurture. Genetically, we are the byproduct of our parents. Then, existentially, growing up around our parents has an impact on who we become. Nature and nurture are extremely powerful forces that set the stage for the future. We embrace some aspects of our parents while rejecting others. Good and bad. Does the child of a world famous athlete have to become an athlete themselves? Some try to follow that path and succeed. Others try but feel too much pressure and fail. Others go in a completely different direction in order to carve their own path. In most cases, the child’s future is a reaction to the parent. 

We see this with Murph and Tom. Murph embraces Coop’s adventuring spirit. The man he dreams of being. While Tom picks up where his dad left off as a farmer. Each follows in their father’s footsteps but in different ways. 

It’s a reminder of how important you are as a parent and the example you set for your kids. 

Why does Murph burn Tom’s corn?

Tom refused to leave the house even though Murph told him that Tom’s wife and son don’t have long to live if they stay there due to how bad their lungs are from the dust. At first, Murph accepts Tom’s refusal. But as she drives away, she has a change of heart. Setting fire to the corn means he leaves the house, which will allow her and Getty to collect Lois and the son and leave with them. Murph also wanted to revisit her old room because she’s on the brink of an epiphany being in the room was helping her figure it out. 

What happens to Tom?

His storyline ends a bit strangely. Murph has her realization that Coop was the ghost and that he left a message in the watch. Tom had just driven back to the house after extinguishing the corn fire Murph had started to distract him. He’s blacked from the smoke. Disheveled. Shocked. He has seemingly no reaction to Murph’s declaration about Coop as the ghost. And then we never see him again. 

We know Coop used the message in the watch to solve the gravity equation and launch the ship that allowed humans to leave Earth. But like…did Tom go? Did Getty save the wife and son? Did Tom get to NASA and reconnect with other people and have a renaissance? Did he refuse and wither in that house while everyone else left the planet? Did he live 10 more minutes or 10 more years? How did he react to knowing his father “came back”? 

Even weirder is the fact that we never see Coop ask about Tom. Maybe it’s something that happens off-camera? But his relationship to both his children was such a big part of the movie that reducing everything to just caring about Murph is…unsatisfying? Or unrealistic? It seems like something you’d want to at least mention, even if the scene is a minute or less. Especially given that Coop had two weeks until Murph arrived at the ship. There was nothing in the house about Tom? No video footage? No note? He didn’t ask anyone if they knew anything? 

So there were no aliens? 

Nope. We have two instances in the movie of the others and both cases are just Coop. First, what he does within the tesseract. Second, when he travels through the wormhole and shakes hands with Brand. NASA had recorded other anomalies that made them believe in the existence of those fifth-dimensional beings. It’s unlikely that every single instance was also just Coop transcending space-time. We do know that the future humans placed the wormhole, saved Coop from the black hole, and built the tesseract. So they exist. 

How do humans end up becoming fifth-dimensional beings? Who knows. Murph did have the quantum data that allowed him to solve the gravity equation. That could be the thing that sets humanity on the course to evolving beyond our current three-dimensional existence. There’s no indication when that would happen though. Dozens of years in the future? Hundreds? Thousands? Millenia? 

We also don’t know what human society even is at that point. Is it just a collective conscience? Are there still individuals? Do they have a physical form? Have we grown eight arms and three heads? 

What was the gravity equation?

Humanity couldn’t survive on Earth. Which meant finding a way to get people off of Earth. This was seemingly impossible, as anything large enough to transport the remaining human population probably couldn’t escape the Earth’s gravity to actually leave the planet. So how do you manipulate gravity in a way that would allow such heavy objects to escape? That seems to be, from the little information we have, the goal of the gravity equation. 

Essentially, once you solve for g (g = gravity), you could manipulate it. Increasing it if you wanted to increase it. Or decreasing it altogether. Something that would allow NASA to launch the Cooper Stations. 

Is there any connection to Tenet or Inception

Nope. 

Why the focus on baseball?

It’s a team sport and we discussed how much working together matters. It’s also classically American. As popular as the NFL and NBA have become, baseball predated them by decades. It was the first major national sport in America. So you could view it as indicative not just the teamwork aspect but of society being back to its roots. While things aren’t quite where they were before the crisis changed the world, we still have baseball. In some ways, it serves as a promise of everything else that will follow. Not just in the world of organized sports but in terms of civilization returning to what it had been. Then surpassing it. 

What was Coop’s job before becoming a farmer?

He’s a former NASA pilot. But he suffered a crash due to a gravitational anomaly. That combined with the government temporarily shutting NASA down is what led to Coop becoming a farmer.

Nolan worked with a scientist on the movie?

Kip Thorne! Who wrote an entire book about The Science of Interstellar. So if you really want to dive into the nitty gritty of the physics, that’s what you’re looking for. Kip has won a Nobel Prize and wrote another book called Black Holes and Time Warps. So Interstellar is right up his alley. 

Why was there a secret NASA facility?

Global society had been decimated enough by climate change and food shortages that the general public saw NASA spending as wasteful. So the government shut it down. Only to soon realize how stupid that was. So NASA resumed operations but in secret, so the public wouldn’t get mad about money being used on something that wasn’t immediately helpful to the myriad of issues everyone now faced. 

Because it was a secret, Cooper had no way of knowing about it aside from the coordinates he would eventually leave himself. 

Isn’t there a time paradox at the center of Interstellar?

Yeah. It’s the classic chicken and the egg situation. Coop in the future leaves the coordinates to NASA for his younger self. But the only reason Coop in the future can do that is because he found them when he was younger. Except he couldn’t have found them when he was younger unless his older self left them there. 

As paradoxical as this may seem, we’re told pretty specifically that the tesseract gives Coop access to various moments throughout space-time. That means what happens isn’t causal, as in “this then that”. Rather, it’s simultaneous. “This and that”. So it’s not that Cooper moved forward through time then circled back. Instead, it’s that each version of him existed in that moment, which is what allowed him to convey the coordinates to himself. 

Now it’s your turn

Have more unanswered questions about Interstellar? Are there themes or motifs we missed? Is there more to explain about the ending? Please post your questions and thoughts in the comments section! We’ll do our best to address every one of them. If we like what you have to say, you could become part of our movie guide!