Ryland Grace (Ryan Gosling) is a gifted science teacher. In other words, he's exactly the kind of person a new space project needs.
Scientists discover a mysterious phenomenon in space that is destroying stars. If they can't find a solution to stop it, the Sun will burn out and humanity will disappear. The only relatively nearby star that has managed to avoid this cruel fate is 12 light-years from Earth. That's where Ryland Grace is sent to try to find the answer, at the cost of eight billion lives.
On the way to their destination, the newly minted astronaut must understand and learn many things they have never encountered before. And make friends with an organism that no other human has ever encountered. Only by joining forces and working together do man and alien have a slim chance of saving the Universe from destruction.