Interstellar: 11 Insane Spoilers Everyone Is Talking About

3. Cooper Saves The Day

As Cooper now has the information from TARS about the singularity, Cooper manages to use the walls of the dimension to communicate with young Murph, creating the dust binary code that she saw at the start of the film, essentially fulfilling a time loop of sorts. With the help of a watch Cooper gave Murph before leaving, he is able to signal to Murph that he is the "ghost", and with that, she is able to finish the Brand equation, which of course allows Earth's remaining citizens to be rehoused elsewhere. Cooper is then "spat out" back into the Solar System, where he (rather conveniently) is rescued by a NASA vessel mere minutes before his oxygen runs out.