Lawrence did not think of himself as a writer of Westerns, so when he was hired to script a horse opera, he focused his writing on relationships and character. One day while on the set of Bonanza (1959), producer David Dortort told Lawrence he wanted to do a story on each of Ben's wives. The screenwriter enthusiastically replied, "Let me do it, I can kill off at least two of them!" Lawrence thought he would get thrown off the set for saying this, but instead was given the task of becoming the writer who scripted the stories with Ben and his wives, all three of whom died.
[on getting hired to write movies for Elvis Presley] My agent called me up and said, "Would you consider doing a movie for Elvis Presley?". And I said, "Who's Elvis Presley?". I had no idea at the time who he was; I had never heard of him. I wasn't a rock-'n'-roll fan in those years. I had grown up in the big-band era. I was a popular song enthusiast as well as a singer. I'd done some singing, and had some training as a saloon singer. So when I went down to meet [producer] Hal B. Wallis, I was a little bit overwhelmed because I'd never heard of Presley. I didn't know what I was getting into. As it turned out, I rewrote a script they had, which turned out to be Roustabout (1964), and then I did two others later on. Those were good, but I remember I was on a week-to-week [contract], and every week at the end of the week I'd pick up my pencils and go home because I figured I was going to be fired.