Leonard was born in the southern region of the United States to Caroline and Harrison McCoy. He had a normal happy childhood until his father was lost in space with the USS Yorktouwn. His mother, apperently, became desperetly unhappy after this event. She died relatively soon after and young Leonard was brought up by his paternal grandfather, T.J. Leonard was strongly influenced in his choice to become a medic by T.J. who was a physician.

Leonard's father was found many years later, when Leonard was already a practicing doctor. His father, however, was suffering from a crippling disease for which no known cure existed. Leonard was taking care of his father himself (ethics?). When the suffering became too great his father begged him to swith of the life support and let him die in peace. After much soul searching, Leonard did as his father requested although he found it very difficult to do so. This decision was made much worse when 6 months later a drug to combat the disease was developed on Altair VI. The whole event had lasting influence on the young McCoy (ST-V)

2266 McCoy is assigned The USS Enterprise NCC-1701, he replaces the retiring Dr. Mark Piper. At First he finds it difficult to work with his new commanding officer, Captain James T Kirk. his own opinions quite often found these two men at odds with each other. It takes a while but McCoy soon finds himself establishing a good working relationship with his captain. They become the closest of friends and have great respect for the others skills. For most of his career he is assisted by Nurse Chapel, they were great friends.

2266 McCoy is assigned The USS Enterprise NCC-1701, he replaces the retiring Dr. Mark Piper. At First he finds it difficult to work with his new commanding officer, Captain James T Kirk. his own opinions quite often found these two men at odds with each other. It takes a while but McCoy soon finds himself establishing a good working relationship with his captain. They become the closest of friends and have great respect for the others skills. For most of his career he is assisted by Nurse Chapel, they were great friends

2268 becomes seriously ill and only has a year to live, he asks Kirk to keep it secret, so he can continue his work on the Enterprise. He has to go on an away mission to Yonada a huge asteroid shaped Space craft. While there he meets a woman named Natira, she falls in love with McCoy and asks him to stay. He does stay with her hoping that in his last days he can find happiness. However in the medical bank on the ship Spock finds the cure for McCoy’s illness, and he realises he must leave Yonada and his Natira. He returns to the Enterprise.

At the end of the five year mission on The Enterprise McCoy retires and returns to Earth to set up a private practice. swearing never to return to Starfleet. 18 months go bye when Admiral Nogura drafts him back using a very seldom used reserve activation clause. He is once again posted to the Enterprise. In command is Admiral Kirk and he begs McCoy to forgive him for being drafted but he needs him for the V'ger Crisis. When the crisis is over he decides to remain for another 5 year mission with Kirk on the Enterprise.

2285 McCoy is training a young crew that will be assigned to the Enterprise, with Captain Spock In command, when Khan Noonian Singh attack Regula 1. They head to the area and during a prolonged battle with Singh Spock is Killed. Before he enters the engine room filled with radiation, Spock swiftly mind melds leaving his Katra in McCoy’s mind .This makes it impossible for McCoy to function and he becomes very ill. Captain Kirk risk all, stealing a ship and returning to the "Genesis Planet" to bring back Spock's Body. This enables a full recovery to health and he is assigned to the new Enterprise NCC 1701A .

2293 While escorting a peace mission for the Klingon Empire, Chancellor Gorkon's ship is attacked, McCoy and Kirk try to save Gorkon's life .The two of them are arrested and sentenced to life in prison in the Rura Penthe Mines. With help from Spock and The Enterprise they are rescued. Dr. McCoy goes on with his career into the next century, influencing the lives of The Next Generation of Starfleet. A highly decorated man, who influences the lives of many souls.