Cooper, Doyle and Amelia went to Miller´s planet while Romilly was studying the gravity in The Endurance (the spaceship). At Miller´s planet, they thought there were mountains, but the giants white estructures were not mountains, they were waves. Cooper and Amelie escaped, but Doyle died trying to escape.
Amelia and Cooper found Romilly 23 years older than them (because of the gravity at Miller´s planet). While they were thinking about what to do, people were dying in Earth. Finally, they decided to go to the Mann´s planet (there was an astronaut called Mann).
Cooper and Amelia arrived to Mann´s planet, where Mann was living. Cooper and Mann fought because Mann was crazy. Finally, Cooper defeated him and went to The Endurance, where he was thinking about the differents forms to save the world. Finally, he decided to go into a black hole because there was the important information.
In the black hole, he found the information to save the world but he didn´t know how to share it. In this moment, he realized that he could travel across the space and time, so he discovered that he was "the ghost" at Murph´s bedroom. Finally, he shared the information with a code (with books and a watch) that Murph discovered (40 years later from the last time Cooper was in Earth).
In the Earth, Murph studied the space, and she was a doctor at this area. When she discovered the information to solucionate the problems (while her father was in the black hole) she created the most important ecuation.
Cooper escaped from the black hole thanks to 5D creatures (the humans in future). He was found in the space by the actual humans, so they took him to an hospital. Finally, he discovered that Murph was 80 years old while he was just 40 (This is because the time is different in the space and in the Earth), but they finally met.