Introduction to the story:
The world is in mid-21st century where more than half of the world's population has been destroyed from famine. Dust storms and lack of food threaten humanity's survival.
Corn is the only and last option for the farmers to cultivate. There is no sign of animal life.
Investment in technology and automobile manufacture is impossible.
The world is coming to an end and so the kids are tested to determine what occupation they will have to take to help the humanity.
Into the story:
Joe Cooper(Mathew McConaughey), a widowed farmer and a former NASA Pilot is living with his father-in-law, Donald, 15-year old son Tom, and 10-year old daughter Murph.
Donald is a down-to-earth man who takes care of the household duties. Tom is a boy of average intelligence whereas Murph on the other hand is a determined and highly intelligent girl.
Cooper is very close to Murph and they share a lot of science and space stuff together. Murph believes her room is haunted by "ghost" because books keep falling off her shelves.
The Cooper family returned back to their farmhouse after attending a baseball league match which got interrupted because of the dust storm.
The window was not closed in Murph's bedroom which leads to dust getting collected in perfect lines like binary codes. Cooper knows those are geographic coordinates caused by gravity variations.
NASA in a bunker:
Cooper follows the coordinates to a secret NASA facility headed by Dr. John Brand, his old boss from NASA accompanied by his daughter Amelia Brand(Anne Hathaway) and a strange looking robot TARS.
Dr. Brand believes that Cooper was brought here by a force. The bunker place Cooper found is actually the remnants of NASA. The place is no longer funded by the government due to scarcity of resources.
Professor explains Cooper about a space mission leaving soon through a wormhole near Saturn. This will take the crew to three potentially habitable planets. Two of them orbiting a super massive black hole named Gargantua which has a solar mass of 50 million Earth's suns.
Ten years earlier, 12 astronauts were sent on 12 different spaceships through the wormhole in search of habitable planets. Astronauts Miller, Mann and Edmond's reported positive signals.
NASA has nobody to pilot the spacecraft to those 3 planets and they want Cooper to go on this mission.
Plan and Travel:
The mission has two plans :
Plan A is to get the bunker(which is actually a centrifuge) into the orbit as a space station and rescue large number of people. Dr. Brand has to solve an equation to get the centrifuge into the orbit by overcoming the gravity.
Plan B is to find the most habitable planet among the three planets and colonize it by repopulating the frozen embryos.
Cooper wants to take this mission for survival of the humanity which made Murph unhappy.
Cooper does his best to convince his daughter and promises to come back. He assures both might be in the same age while he returns, by giving her a wrist watch to compare time.
Murph refuses his assurance and her bookshelf is communicating with her in Morse code to "Stay". Despite her pleas and one more book falls from the book shelf, Cooper disregards and says goodbye.
A space shuttle rockets away from the Earth in high speed carrying Cooper, Amelia Brand, two other scientists(Doyle and Romilly), along with TARS and CASE robots on-board.
The space shuttle dock with the ring shaped Endurance which has all their needs for the space travel. They put themselves into a plastic-covered water cyrosleep bed for the two- year journey to Saturn.
The Endurance is orbiting the Saturn and Cooper is out from cyrosleep and reviewing video messages from the family.
The Endurance crew comes upon a wormhole which provides an easy gateway to reach the three planets in the next galaxy.
The crew take off for a rough ride and reach their first mission, Miller's planet. During the time through the wormhole, Amelia feels she touched someone's hand. They decide to stop at Miller's briefly as it is in close proximity to Gargantua black hole, which has a severe gravitational dilation with each hour spent on the surface would cost seven Earth years.
Cooper, Amelia, Doyle and CASE decides to survey the planet quickly in few minutes whereas Romilly stays in the Endurance.
The surveying crew find shallow water and wreckage of Miller's ship, who apparently died even though she sent a thumbs up beacon 10 years ago.
The crew thinks there are mountains at the distance that turns out to be giant tsunami waves. It take hours and costs Doyle's life while trying to escape tsunami and reach the Endurance.
Cooper and Amelia return back to Endurance and find aged and gray Romilly after 23 years. It is now year 2090 on earth.
They are all beyond crushed. Amelia is relieved to know her father is still alive. Cooper reviews and breaks down after watching 23 years of recorded videos. In one video his 17-year old son Tom shows a picture of a girl next to him. In the next video, Tom introduces Cooper his grandson. In the following video, it is 40-year old Tom reveals that Donald is dead and he believes Cooper is dead or missing.
Cooper gets live recording from Murph after 25 years of her silence. The stubborn and saddened Murph wants her father to know that he fails to fulfill the promise he made to come back because she is now 35 years of age which is the same age he was when he left the Earth. The feel of betrayed her badly is like a knife has been plunged into his heart and the worst part is there is no way to communicate back to her.
Murph is now working for Dr. Brand to solve the gravity equation to get plan A rolling.
Endurance crew debate on which planet to visit next because they have enough fuel to visit one of them before they head back to earth.
Amelia wants to visit Edmond's planet because his planet appears to be a better prospect, but Cooper wants to visit Mann's planet as he is still transmitting his beacon.
On Earth, Murph returns to her home where Tom is taking care of the farming with the family. He has just torched the crop field because if the spreading blight. They believe farming will soon produce nothing. Murph has dinner of corn souffle and corn-on-the-cob with Tom, his wife Lois and son Coop. She discovers Coop has a bad cough because of nitrogen level in the atmosphere.
Murph is back at the NASA bunker and learns Dr.Brand is dying. He confesses to her that plan A is not possible and he lied to her about solving the gravity equation. She believes her father knew all about Brand's scheme and escaped Earth leaving everyone else to die. Murph sends a video message to Amelia about her father's death and said the whole plan A thing is a lie.
The Endurance crew reached Mann's planet where it is cold, covered with glaciers and has a poisonous atmosphere of methane filled with ice clouds. Cooper rescued Dr.Mann(Matt Damon) who has been in cyrosleep for over 35 years. He explains how the lower part of the planet is a beautiful place is to live with 80% of Earth's gravity and possibly even a source of fresh water.
When Amelia explains plan A is a lie after watching Murph's video, Mann assures that the equation was solved long ago. The only way to make it possible is by getting the data from inside a black hole, which is impossible without being killed.
Back on Earth, Murph and her boyfriend, Dr.Getty who is another NASA physicist are driving in her jeep watching people migrating the town searching and hoping for a better life. Murph knows Dr.Brand gave only a part of the equation and the remaining part of the equation can be solved when it comes from a black hole. She has a gut feeling that the co-ordinates of dust on the floor of her bedroom long ago gave her a hint. She believes the "ghost" tried to comfort her by telling something to help save humanity.
When Space and Earth meets:
Mann is showing Cooper the icy and forbidden world.
Murph is back at Cooper's home with Dr.Getty examining Tom's son for his lungs problem.
Dr.Mann pulls off Cooper's voice beacon and push him off the cliff.
Tom is outraged and hit Getty in his face, hearing his comment that they will die if they stay.
Mann reveals to Cooper that the planet is uninhabitable and he sent the signal so he could take Cooper's spaceship back to Earth.
Murph confronts Tom that their father escaped Earth leaving them behind to suffer which Tom refuses and tells her to leave.
Mann is trying to kill Cooper by breaking his helmet's visor, allowing ammonia-rich air to suffocate Cooper. However, Cooper manages to reaches his voice beacon and call out Amelia for help.
Murph and Getty are driving back to NASA but in a fit of rage, she pulls over and pours gasoline over corn crops and set them on fire, in order to divert Tom so that she can check her bedroom in the farmhouse.
Cooper has been rescued by Amelia. Mann's living quarters has exploded killing Romilly, as he was trying to retrieve data from Mann's robot KIPP. TARS is rescued by Cooper from the rubble and with Amelia they all set to leave the planet.
On Earth, Tom's family is out of the house to control the fire and Murph is now in her bedroom trying to make sense of the past.
Cooper and Amelia are leaving the planet, Mann is also on another shuttle trying to leave and refuses to listen to their pleas to not attempt to dock with the Endurance. Mann manually attempted to dock, ignoring repeated "imperfect lock" warnings. It results in the expulsion of air into space carries him with it and the collision causes explosion.
The Endurance is now out-of-control and Cooper tells Brand that he is going to dock with it, even though it is in rapid rotation. Cooper is able to dock despite the enormous centrifugal g-force. However, they are unable to go back to Earth and had to go to Edmond's planet as the life support is being destroyed.
To reach Edmond's planet, they have to slingshot around the black hole Gargantua. Cooper and TARS detach their respective shuttles without Amelia's knowledge to reduce ship's mass. They sacrifice themselves and get sucked into the black hole. Amelia is outraged with Cooper and left alone to Edmond's planet with CASE. Cooper realizes the cost of orbiting the black hole due to gravitational time dilation will be 51 years, but takes the chance.
Gravitational force rips Cooper's shuttle apart and the computer in his ship tells him to eject himself and without reluctance, he does it.
Cooper descends in the black hole towards a grid full of cubbyholes thinking he is dead and finds himself in some sort of afterlife, completely unaware of the surroundings which nearly resembles a tesseract.
He hits an object with a bunch of others that looks like books stacked and knocked one down, revealing 10-year old Murph reacting to the objects falling in her bedroom. He is screaming out for Murph but she walks away and doesn't hear him. He sees Murph in another part of the grid pleading him not to leave for the mission. Cooper watches this begging himself not to leave and to "stay" using Morse code by knocking the books off the shelf. Then there is adult Murph at the bedroom realizing that her father was the ghost communicating with her. Now it is all making sense to her and she is no longer angry on him, yet trying to find out what her father is trying to signal her.
TARS gets Cooper out of the grief-stricken state and tells Cooper that some fifth dimensional things sent him there to communicate with Murph. Cooper realizes that the mission was not a mistake and he will get done what he needs to. Murph has been the chosen one to save humanity and Cooper is the one chosen to engineer it.
He sends the coordinates to himself at the farmhouse to NASA at the beginning. He also sends the data from the black hole through TARS via Morse code to the wristwatch he gave Murph before he left, which is the gravity equation. Preteen Murph puts the watch back on the shelf for Cooper to add the equation. Adult Murph picks the wristwatch from the old box seeing the second hand with Morse code realizing it is the key. Murph returns to NASA bunker and solved the equation using data from the wristwatch.
Back in the black hole, the tesseract is now closing up, with Cooper convinced it all worked and comforted TARS everything is okay that the future human beings constructed it all to make things happen. He comes across the Endurance when it passes through the wormhole and touched Amelia's hands, then knocked unconscious into the orbit of Saturn.
New life for humanity:
Cooper wakes up to find himself in a hospital bed with doctor jokingly telling him he is 124 years old, but still looks the same in his mid to late 30s. He adds that he has been saved by the space rangers. Cooper looks outside the window of his room with the kids playing baseball. Cooper is told he is on Cooper station orbiting Saturn. Murph is still living on another space station and she will be there to visit him. Cooper is delighted to see Plan A is worked and NASA bunker is now the space station to sustain human life.
Cooper is released from the hospital and given a tour around the place. He finds the environment is new and artificial. He finds TARS and admits how he is dissatisfied at the artificial surroundings an pretending to be home.
Cooper is in a hospital room where elderly Murph is living her last days of life. A nurse tells Cooper that her family is here. He carefully opens the door to see over a dozen of his descendants from small children to middle-aged adults around her bed who are puzzled by his appearance. Cooper's main interest is to see her daughter to assure her he was the "ghost". Murph is delighted to see him but doesn't want him to see her die.
Knowing the space station is not where he belongs, Cooper takes Murph's advice to travel to Edmond's planet where Amelia started colonization. It is a desolate place resembling Mars but the air is breathable and can sustain life. Cooper steals one of the new generation ranger ships with TARS and travel for a better future to Edmond's planet.