Interstellar: Ending Explained (In Detail)

In 2014, free from the clutches of Warner Bros’ caped crusader property, Christopher Nolan embarked upon Interstellar, a filmmaking endeavour that dwarfed his earlier work: A true-blue sci-fi drama set in the future about a mission to save humankind, headlined by Matthew McConaughey, and co-starring Anne Hathaway, Matt Damon, Michael Caine (naturally), and Jessica Chastain.

The Departure

The year is 2067 and the human species is staring at possible extinction due to widespread famine. Cooper (McConaughey), a former astronaut, has turned to farming, but an aberration in his physical reality brings him and his curious daughter Murph (Mackenzie Foy) to a secret NASA facility where preparations are underway to launch a mission that will find a planet beyond the solar system fit for human habitation. The data from those planets is likely what’ll save the lives of those on Earth. The mission is already crewed by three scientists, one of them being Amelia Brand (Hathaway), the daughter of the lead scientist Dr. Brand (Caine), who offers Cooper the chance to pilot the craft “Endurance”. The ex-astronaut agrees, though not before his daughter breaks down, refusing to bid him farewell.  

The Mission

The mission involves travelling to another galaxy through a wormhole near Saturn, which takes nearly two years. The first planet, - Miller’s Planet - is a water world where every hour amounts to seven years on Earth, an instance of time dilation. The waves wash away a crew member, and when Cooper and Amelia return to the craft, their surviving crewmate has aged twenty-three years. As they catch up on over two decades worth of correspondence, Cooper sorrowfully realises that he missed seeing his children grow up.

Back on Earth, Brand confesses to Murph the true purpose of the mission – to colonise another planet, rather than data that could help the Earthlings. Brand dies soon after, leaving a devastated Murph to question her father’s reasons for leaving her and her brother. Unwilling to give up, she gets cracking on the problem of mass exodus that Brand had abandoned.

Endurance reaches the second planet, where a prior mission’s leader Mann (Damon) is awakened from cryostasis. Mann takes Cooper around the planet, things seeming perfectly normal till he suddenly attacks Cooper, revealing that he faked all the data he sent to NASA, and that he and Dr. Brand always knew saving humanity was impossible and colonisation was the only way forward. He tries to kill Cooper, and when that fails, he steals Endurance’s lander to dock with the main craft. Cooper and Amelia give chase, and Mann is killed by an explosion when he attempts to force his way onto the craft.

Cooper and Amelia decide it would be best for her to get to the third planet, charting a gravity-assist path to that end before Cooper detaches himself, falling into the black hole’s event horizon: A point of no return.

The Return

Cooper falls into a five-dimensional tesseract where time is a physical dimension. He looks around the environment and realises he is behind Murph’s bookshelf. Using gravity, he communicates with Murph through a watch he gave her, simultaneously realising that his future self initiated the mission in 2067, and that the tesseract was created by a subsequent generation to save all humankind. He then relays to Murph the data he has on blackhole gravity, allowing her to solve the equation Dr. Brand had abandoned and initiate measures to save everyone. 

Cooper is then ejected through the wormhole into Saturn’s orbit, where he is found in 2156 by crafts known as Rangers, who take him to an O’Neill cylinder named for Murph (now played by Ellen Burstyn), who is finally reunited with her father.

Interstellar ends with Murph insisting that Cooper leave, because “No parents should see their child die”, a nod to her brother Tom’s experience with losing his firstborn. Cooper steals a Ranger and makes for the third planet, where Amelia is setting up a new colony with the intention of repopulating it, as had been the intention all along.

The journey to the tesseract has altered Cooper’s understanding of human survival and he now sees the need to accept the reality that he is faced with: Life on a new planet is the way of the future.