When giant lizard like creatures come out of the ocean and attack every city killing millions. All the nations come together and build giant robots called Jaegers. They are piloted by two individuals who are linked up to them mentally. While they are able to defeat the creatures whom they call Kaijus, eventually they adapt and even the Jaegers can't stop them. So all the heads of the nations decide to stop the program and to try other tactics. But Pentecost the man in charge of the Jaeger program decide to continue the program. He recruits Raleigh Becket a former Jaeger pilot who left after his co-pilot who's also his brother died. He tries to find a compatible co-pilot and when he finds no one, he gives Pentecost's assistant, a girl named Mako a chance. And when she proves to be the best, he wants her but Pentecost doesn't think she's ready. And when they try to hook up with their Jaeger, he sees what she's been through, which is what Pentecost was worried about. In the meantime, one of the scientists working on how to defeat the Kaijus thinks he found a way but he needs an actual Kaiju brain so Pentecost sends him to see a man who uses Kaiju remains to make a profit, so that he could get a Kaiju brain.