For on the last day of 1971, Murphy's screen partner Peter Duel was found shot. Yet the filming of the Alias Smith And Jones series went on without a break. Because of contract problems it couldn't be dropped or even decently delayed.
Within 72 hours of his friend's death, Murphy was back at the studios, re-shooting the dialogue he had been filming with Duel.
Because one episode of the series had not been completed when Duel died, Murphy had to re-play the same lines opposite another actor--Duel's replacement, Roger Davis.
The film company was criticised for the seemingly indifferent way in which the show went on while Duel's body was hardly cold in the grave.
It still unnerves Murphy to talk about the tragedy. Duel was his friend on and off the set. Yet he explains: "We had to carry on. A lot of people relied on the series for a living... the production crew, the camera boys.
"But it was the hardest thing to do. Pete and I had worked up a big rapport in the series. A real thing together. Yet I was there playing over the same routine, the same spoofing and kidding with Roger. It was strange, not real at all.
"I don't think anybody knew much that day. Or how they got through it. But I remember thinking it was very hard on Roger Davis. How he must have felt.
"Nobody wants to take over in that kind of way."
Duel was not regarded as a quitter. He was a sensitive and serious young man, full of compassion for wounded, hurt things--whether people or animals. If anything, he cared too much.
Murphy understood this. The moment he heard of Duel's death, he went to his home to make sure the actor's three dogs were cared for.
It was a friend's gesture to a man who had once plunged into the Hudson River to save a stray puppy.
Murphy says: "Sure, he seemed happy that last day. We can all seem happy. Act happy.
"But that isn't' the answer to anything, is it? Nor are words. Basically, I'm always asking people to get under my words.
"Discover me, dig me out. Get to the real thing. I don't always make it easy. I can appear cool and aloof."
Murphy is 30 and bears more than a passing resemblance to Paul Newman, although he is tired of the comparison. He arrived in London with one medium suitcase and a holdall--suitable luggage for a young man who professes to be a student of life. The graduate look.
For the past few months, his break from filming Alias Smith And Jones, he had been making the occasional stage appearance in the States, following up his hobbies--ski-ing, tennis, girls--and touring Europe.
He drifted into town from Oslo. There, it seems, he was something of a sensation with the ladies. Murphy doesn't smoke or drink. He he does like girls.
Over tea in his suite at the London Hilton, Murphy said: "I select one girl, chase her... and move on. But for the time, I try to make the relationship an important one.
"I like them to be very positive. If there is the least little negative thing, I will pick it up immediately and shy away. Also, I value honesty."
The girls in London, it seems, have a positive interest in Murphy. While we talked, the telephone rang repeatedly.
Each time, it was a girl admirer, wanting to talk to--or, hopefully, date--the handsome young star. How did they know where he was staying?
Murphy grinned: "They know you're in town and ring around all the hotels until they get the right one."
There was one girl in his life--the one who encouraged his acting--that Murphy finds hard to forget.
He said: "She taught me how to love, how to feel towards life. She made me want to relish every moment... to make myself useful in life as a positive force.
"From then on I knew I had to find something that I wanted to do in life and do it for the good of all concerned.
"She planted my seed in acting, got me out of drifting and being lost and on to that positive track."
Drifting was Murphy's problem for a long while. He was born on a farm at Jonesboro, Arkansas. He was always going his own way. His home was comfortable and middle class, but he hated it.
He said: "I wouldn't go along with my parents' programming. Even now my contact with them isn't close. I see them, maybe, twice a year.
"I was a longer. I found it difficult to communicate with people. And there was a lack of feeling which comes from the fear of being hurt. I wouldn't reach out to people emotionally.
"Acting helped that. It taught me to feel... if I get hurt, I get hurt."
His career has gone neatly. No problems. When he graduated from the University of Illinois, he enrolled with the Pasadena Playhouse. An agent spotted him while doing a play in Los Angeles and sent him to a film studio for an audition.
He spent two years as Robert Stack's sidekick in television's The Name of the Game, then Alias Smith And Jones came along.
He said: "Pete was all set up for his part. I didn't think I had a chance. There were four chairs outside that audition room and five of us waiting. I was last, so I had to sit on the floor."
"What tipped it for me was my hair and eye-colouring. The others were dark like Pete. I was the contrast."
Back home in Hollywood, he has a one-bedroom apartment near the studios. It is filled with books, mostly about philosophy. He says the place hasn't much style or room.
A girl-friend lived there with him for a while. He recalled: "The experience taught me that I am going to need a very big home with a room for myself that nobody can get into. I'm going to have to preserve my own private area as a male, always."
The fact that the girl eventually walked out on him proved the atmosphere was nothing less than claustrophobic. "That hurt me," he said. "But a lot of that was ego-hurt."
"I ski-ed a lot afterwards. That's the way I got over that relationship. A lot of my dates after that were girls who went ski-ing with me."
Pete Duel once told an interviewer: "If you're in the public eye, it very often makes for trouble in your private life. That's something I simply cannot handle."
But Murphy has worked out his own approach to the success of Alias Smith And Jones. The fan following is heavy. When the last series is repeated on BBC-2 in the autumn, it will send the requests for autographs and pictures soaring.
Murphy said: "I have this feeling I belong to everyone. Psychologically, I'm suited to being an actor, being public property."
"Gradually I have taught myself to accept everything. I am willing to live in a certain way to survive. You must keep open to everything in life. It has to move on.
So Alias Smith And Jones moves on, with a new co-star for Murphy in Roger Davis. Duel's death was a shock... a tragedy. But when the filming had to go on, Murphy realised it had to be.
As his philosophy demands: "I had
to accept it."