Interstellar sees the Earth utterly ravaged by famine and dust clouds, leading NASA, now underground, to face the fact our future lies in the stars. They intend to use a wormhole to travel to a far off galaxy and find a new habitable world, coming up with two convoluted schemes; Plan A has the population of Earth transported to this new world; Plan B leaves those on Earth abandoned, with a new colony based on pre-made embryos forming the basis of a new humanity. Through the film Cooper (Matthew McConaughey) and Amelia Brand (Anne Hathaway) scout out three potential planets orbiting a black hole that could hold life. Due to dilation caused by the black hole's stronger gravity, time passes slower than for those back on Earth, where things get steadily worse; it becomes apparent that Plan A was a lie, with the science required impossible, leaving Earth-born humans destined to extinction. At the end, with the first two planets clearly uninhabitable and the third almost impossible to reach, Cooper and Brand come up with a crazy plan. They're going to slingshot the Endurance, their space ship, around the black hole. It transpires Cooper has to jettison himself and robot TARS to provide the necessary thrust. He flies through the singularity, some crazy stuff goes down and he wakes up in an new human colony. Reuniting with his daughter briefly, he sets out to find Brand and the new world. That's the basic story of the film, but the ending is much involved than that. Before we look into what the film's trying to say, let's first get our heads around the final twenty minutes of Interstellar.
