The Federation along with a group scientists are collaborating on a project called Genesis. Which is a plan to bring a dead planet to life. So far the preliminary experiments have been a success. Now for the next phase which is to actually bring a planet to life, a dead planet is required. So the Federation sends a vessel, the Reliant to find one and it's first officer is former Enterprise crew member Pavel Chekov. They come across what appears to be a dead planet in the Ceti Alpha system. But the sensors detect something which makes it not a dead planet. But the Captain thinks maybe they can remove it, so he and Chekov go and investigate. But they find what appears to be a life pod. When Chekov sees something, he tells the Captain they should leave. But they are captured by the inhabitants. When they meet the leader, Chekov recognizes him as Khan, the bio engineered human from the late 20th century whom Kirk found 15 years ago. Who tried to take over the Enterprise and kill Kirk. But Kirk subdued him and left him on Ceti Alpha 5. Khan reveals that Ceti Alpha 6 exploded shortly after they were left and the force shifted Ceti Alpha 5 orbit which turned the planet into a wasteland. Khan deduces that Chekov and the Captain thought they were on Ceti Alpha 6. When he asks them why they are there, they don't answer. That's when Khan puts a wormlike creature in them, which makes them susceptible to suggestion. Upon learning why there are there, Khan takes the Reliant and tries to steal Genesis and get back at Kirk. He starts by making Chekov contact the scientist in charge of Genesis and telling her that Kirk has ordered him to take possession of Genesis. She then calls Kirk who has no knowledge of what she is talking about but before they can talk any further, they lose contact. Kirk who's now an Admiral, is accompanying Mr. Spock who is now in command of the Enterprise, who is taking some cadets on a training run. But now he tells them they have investigate what is happening. So they go and meet the Reliant, that's when Khan attacks the Enterprise crippling it. Khan then calls Kirk and demands that Kirk turn himself and all data on Genesis. Kirk uses the time to come with a counter move which he executes. So while Khan repairs the Reliant Kirk heads off to find the Genesis scientists.