pain. Shortly after the suicide, a cure was found for his father's disease, and McCoy had carried the guilt about it with him until Sybok's intervention. In Star Trek VI: The Undiscovered Country (1991), McCoy and Kirk escape from a Klingon prison world, and the Enterprise crew stops a plot to prevent peace between the United Federation of Planets and the Klingon Empire. Kelley reprised the role for the "Encounter at Farpoint" pilot episode of Star Trek: The Next Generation (1987), insisting upon no more than the minimum Screen Actors Guild payment for his appearance. McCoy had attained the rank of admiral in the Trek timeline when this episode was aired, and he is stated to be 137 years of age. He went on to become chief of Starfleet Medical, with a special rank known as branch admiral. The fictional book Comparative Alien Physiology was written by McCoy, and was required reading at the Starfleet Medical Academy through the 2370s. In the 1973 Star Trek: The Animated Series episode "The Survivor", McCoy mentions he has a daughter, Joanna. Although Chekov's friend Irina in the original series episode "The Way to Eden" was originally written as McCoy's daughter, it was changed before the episode was shot. Reboot film series In the 2009 Star Trek film, which takes place in an alternate, parallel reality, McCoy and Kirk become friends at Starfleet Academy, which McCoy joins after a divorce that he says, "left [him] nothing but [his] bones." This line, improvised by Urban, explains how McCoy earned the nickname Bones. McCoy later helps get Kirk posted aboard the USS Enterprise. He later becomes the chief medical officer after Doctor Puri is killed during an attack by Nero. McCoy remains aboard to see the Enterprise defeat Nero and his crew, with Kirk becoming the commanding officer of the ship. The Guardian called Urban's portrayal of McCoy in the 2009 film an "unqualified success", and The New York Times called the character "wild-eyed and funny". Slate said Urban came closer than the other actors to impersonating a character's original depiction. Development Kelley had worked with Star Trek creator Gene Roddenberry on previous television pilots, and he was Roddenberry's first choice to play the doctor aboard the USS Enterprise. However, for the rejected pilot "The Cage" (1964), Roddenberry went with director Robert Butler's choice of John Hoyt to play Dr. Philip Boyce. For the second pilot,