DeForest Kelley was the far out space doctor in Star Trek for a total of 76 episodes from 1966 to 1969. He played the role of Doctor Leonard "Bones" McCoy alongside William Shatner, Leonard Nimoy, Nichelle Nichols and more. 

In the series, Dr. McCoy treated everyone from space aliens to humans. Being a doctor seemed to come natural to Kelley, and maybe it was. Before starting his acting career, Kelley thought about becoming a doctor in real life. With his experience in the Trek world, we could see it for him. 

In a 1968 interview with The Desert Sun, Kelley said he was inspired to become a doctor by his uncle, who was a distinguished physician in his hometown of Atlanta.

Even though he had the support to become a doctor, Kelley went a different route.

In a 1968 interview with The North Adams Transcript, Kelley said taking the role on Star Trek led him to more opportunity than he could have ever imagined.

"I'm eternally grateful for Star Trek and what it's done for me," he said. "I had been in the business 20 years and even made two pilots, which never sold. I had resigned myself to the fact that I would never have a series. I still can't get over the popularity this show has brought me. It gave me renewed faith in myself." 

During the Apollo 7 flight, Kelley said he felt naturally involved by playing Bones on Star Trek. According to the interview, Kelley sent out the following telegram to the space program: 

"I do not make house calls but under the circumstances would be pleased to beam aboard and take care of the common cold." It was even signed by Bones. 

According to the interview, Kelley said in developing his character as Dr. McCoy, he had to become a doctor. Mindset wise, that is. 

"It's been my experience that there are very few physicians who give the patient any kind of warmth," he said. "I've tried to inject warmth into McCoy. I've tried to make him a human being, a man who cares."

Even though Kelley technically was a doctor in the series, we could only imagine how different Kelley's life would have been if he would have become a real doctor, as he had hoped to become when he was young.

"If I could have picked any role in the series, I would have picked McCoy," he said. "He reminds us that the sci-fi world is still troubled by humans."