The cruelest scene in Interstellar has no dialogue.
Cooper and his teammates land on Miller’s planet, racing the clock to retrieve data. The planet sits close to the black hole, and gravity has stretched time there. One hour on the surface is seven years on the mother ship. The mission goes wrong. A few hours slip away. When they return to the ship, their crewmate has been waiting for twenty-three years. Cooper sits down and starts watching the backlog of messages. His son grows from a teenager into a young man, sends word that he has become a father, then reports that Grandpa has died, and eventually says he will stop sending messages altogether. His daughter Murphy finally sits down in front of the camera at twenty-four, saying that today is her birthday, and that she is now the age he was when he left. Matthew McConaughey plays this for over a minute, from a smile to trembling to collapse, without a single line. Nobody in the theater can sit still through it.
Time dilation is a legitimate concept from Einstein’s relativity. In other science fiction films it is a setting; in this one it is an instrument of torture. The farther you travel and the stronger the gravity, the faster the people who love you grow old. In those few hours Cooper misses half of his son’s life. By the time he sees a photo of his grandson, the boy has already been alive for years. A screen is a foot away, with twenty-three years in between. Some call this a gulf between near and far; physicists call it gravitational time dilation. For a father, the two phrases say the same thing.
The backdrop of the story is an Earth dying slowly. In the near future, blight sweeps the globe, wiping out crops one species at a time, and dust storms yellow the sky every few weeks. Humanity has stopped exploring the stars. Official textbooks even rewrite the Moon landing as a hoax, to keep children’s ambitions down on the farm. Cooper was once an engineer and a pilot; now he grows corn, holding a farm together with his father-in-law, his son, and his daughter. Strange things happen in his daughter Murphy’s bedroom. Books fall off the shelf by themselves. She calls it a ghost. Cooper doesn’t believe in ghosts. He believes in gravity. During one dust storm he notices that the falling dust has arranged itself into coordinates on the floor, pointing to a secret base. NASA is still alive, hidden underground. They have found a wormhole near Saturn leading to a dozen candidate planets in another galaxy. Cooper is chosen to go.
Before departure he has a blazing fight with Murphy. She doesn’t want him to go. He says he will come back. That promise becomes the heaviest thing in the entire film. On the far side of the wormhole he goes from planet to planet, and every step is a bargain struck with time.
The science in this film is genuinely hard. Kip Thorne, winner of the Nobel Prize in Physics, served as scientific adviser and set one rule: nothing on screen may violate the established laws of physics. The wormhole is a sphere, and what you see through it are refracted galaxies, all of it calculated strictly from the equations of general relativity. The accretion disk of the black hole Gargantua came out of new theoretical work by Thorne’s team, simulated with purpose-built software, and it is regarded as the most physically accurate visual rendering of a black hole in film history. When humanity captured its first real photograph of a black hole in 2019, Thorne came out to explain the three differences between the photo and the movie. Nolan has said that without Kip, this film would simply not exist.
But what keeps millions of people rewatching it is something else.
It is that bookcase room. Cooper finally falls into the black hole and is trapped inside a five-dimensional space whose far side is the bookshelf in Murphy’s bedroom. Every year of her life, from birth to adulthood, unrolls before him. He finally understands that the ghost who knocked the books down all those years ago was himself. Across the dimensions he passes data to his daughter, using gravity, using the twitch of a watch’s second hand. He once encouraged little Murphy to investigate the ghost. Murphy grew up, threw the watch her father left behind into a fire, then snatched it back as if possessed. She reads the Morse code in the second hand, solves the gravity equation the old professor never cracked in a lifetime, and lifts all of humanity onto a space station.
So that line in the film keeps proving true. Dr. Brand says it first: love may be the one thing that can cross dimensions. At the time everyone takes her for a fool. Cooper proves it with action. Why was Murphy the one chosen to receive the message through gravity? Because the thread between father and daughter was the only one that stayed taut through twenty-three years without snapping.
The name Murphy gets turned inside out too. The usual reading of Murphy’s law is that whatever can go wrong will go wrong. Cooper gives his daughter another version: whatever is possible will surely happen. True of disasters, and true of salvation. Humanity’s rescue was possible, and so it came to pass.
The score deserves its own paragraph. Hans Zimmer built the film’s dominant voice on the pipe organ, an instrument whose architecture and sound resemble a spacecraft’s afterburner. One chord of that church-like reverberation and awe at the stars stands up without a single line of dialogue. Zimmer began composing before the film was finished. Nolan handed him a one-page fable and never told him it was science fiction; Zimmer only found out after he had written the music. In this film the music is not accompanying the story, it is the story. Cornfield Chase climbs right along with the chase across the cornfield, and it still lives in countless playlists today.
Dylan Thomas’s poem recurs throughout the film. Do not go gentle into that good night; rage, rage against the dying of the light. Professor Brand recites it on his deathbed, and again as the ship lifts off. The poem was written as a roar against the end of a life, and Nolan fastens it to the dying day of human civilization. Earth is that good night, and humanity refuses to walk gently into it, so some look up to find a road while others stay behind to guard the equations. Some critics have called the film sentimental, accusing Nolan of dressing a father-daughter drama in the clothes of physics. That charge is not entirely unfair. But twelve years on, the people who once picked at its flaws are rewatching it too, and what they watch has changed. One comment puts it plainly: ten years ago I saw science fiction; now I see my father.
The character of Cooper is hard for many fathers to bear. He sets out to give his children a future with air in it, and the price is absence from their growing up. Leaving your children for your children is a contradiction with no tidy resolution. The adult world is littered with choices like this: earn money far away or stay close, chase the career or tend the family. Cooper picks the former and spends the rest of the film paying for it. It isn’t that he doesn’t want to turn back. In the dimension where he is trapped, the road back is sealed, and all he can do is watch his daughter grow up year by year through a bookshelf.
At the end, Cooper is rescued from the five-dimensional space and wakes to find Murphy in her nineties, white-haired in a hospital bed. Father and daughter are reunited, the daughter now decades older than her father. Holding his hand, she tells him to go find Brand, who is alone on another planet building a camp. Cooper takes a ship and sets out again. Think about it too hard and the scene is merciless, yet the film plays it calmly, as if to say that a father cannot dodge farewells, so he might as well keep showing up for them, one after another.
I know some will ask whether the science holds up. Thorne wrote an entire book answering that question, laying out line by line what is real and what was loosened for the sake of the story. There may well be no wormholes in the real universe; holding one open would require exotic matter with negative energy, and nature may not be willing to provide it. But the withering Earth at the film’s opening requires no speculation at all. UN reports say a quarter of the world’s farmland is degrading. Dust storms and vanishing species need no trip into the future to find. Nolan shot the apocalypse so close it resembles a weather forecast, and that may be why the film grows heavier in the chest the older it gets.
The night after watching it, I went downstairs for a walk and looked up for stars. The city light was too bright; I saw nothing. On the way home I thought of my own father. He spent half his life on engineering projects away from home and never once came to a parent-teacher meeting from my primary school through high school. I resented him for it. Now it is my turn to earn a living elsewhere while my child calls out “Papa” over the phone, and I am beginning to understand what that bookcase room means. Every parent owes their child a stretch of company, and everyone finds their own way to settle that account. Cooper’s way was to tap the twitch of the second hand where his daughter could read it.
Love may not truly cross dimensions; no physicist would dare put it that way. But a father’s obsession with getting home is, in this universe, the most stubborn form of gravity there is.
The second hand is still ticking. Those who learn to hear it still have time.