In 2285, the USS Enterprise, which was damaged in the battle with Khan, returned to Earth's spaceport for repairs. Kirk was still grieving over Spock's death. Dr. McCoy showed various abnormal behaviors: such as breaking into Spock's original cabin without permission and talking nonsense, and he was finally sent to the hospital for a mental examination. Scotti was assigned to the USS Excelsior. Starfleet Command issued a ban on the newly formed Genesis. Kirk was told that the Enterprise was about to be decommissioned. Spock's father, Sarek, found Kirk and told him that Spock's body must be returned to Vulcan, otherwise his soul would not rest in peace. Sarek asked Kirk to return to Genesis, retrieve Spock's coffin and bring it back to Vulcan-and Spock had a mind fusion with McCoy before his death, so McCoy with Spock's soul must also go to Vulcan. However, Starfleet refused to let the old Enterprise leave the spaceport. McCoy, who heard the news after coming out of the hospital, attempted to recruit a spacecraft to return to Genesis. He was arrested during an argument with others, but this did not affect the entire plan: with the help of Kirk, Scott, Sulu, Uhura and Chekov, McCoy successfully escaped and boarded the abandoned Enterprise together. In order to avoid being chased, Scotti also destroyed the engine of the Excelsior. The six partners risked destroying their lifelong careers and drove the Enterprise to Genesis. In the meantime, the Klingons learned about the Genesis Project and Genesis. Fearing that the Federation would transform it into a new weapon, Captain Kruger led a Klingon Raptor battleship to seize or destroy this strategic weapon. On the federal starship Grayson, Dr. David Marcus and Captain Sasuke conducted scientific observations in orbit around Genesis. They soon discovered life forms on the ground. Driven by curiosity, the two of them teleported to the surface of the planet and discovered Spock's empty coffin. Following the readings of life forms, they discovered the living body of a young Spock: growing at an incredible rate, but without consciousness or soul. The Klingons also arrived at Genesis at this time, destroying the Grayson and taking Sasuke, Marcus, and the young Spock hostage. Soon after, the Enterprise arrived at the Mutara Sector and was quickly paralyzed by Kruger and his group of Klingon warriors. As the Klingons threatened to take the lives of the hostages, Kirk used a ruse to regain control of the situation, but failed. David Marcus was then killed by the Klingons. With no other choice, Kirk surrendered to the Klingons. In a desperate attempt to regain the upper hand, Kirk activated the Enterprise's self-destruct sequence. The Enterprise's crew then teleported to Genesis and watched the Enterprise destroy in a flash of light, taking most of Kruger's warriors with it. Kirk and his team eventually rescued Spock and Sasuke from the Klingons, and killed Kruger in a one-on-one battle. Due to the unique power of the Genesis, Spock's body was reborn, and grew rapidly as the Genesis aged. When Spock left the unstable Genesis, he was just the age before his death. While boarding the captured Bird of Prey, the Genesis began to explode violently. Under Sarek's protection, the Bird of Prey arrived at Vulcan. After undergoing a dangerous "Futubang" ritual, Spock's soul left McCoy's mind and returned to his own body. The ritual was ultimately successful, and the resurrected Spock began to reminisce about his past and friends. He asked the Enterprise crew why they risked their lives and careers to rescue him; Kirk told them that sometimes you need to "sacrifice the little for the greater good."