from “Divided Soul/The Life Of Marvin Gaye” David Ritz

"Years back, when we were still in Detroit,
Berry saw my acting potential, even before he
started pushing Diana. He wanted to do the Sam Cooke story
and have me play the lead. This was in 1964 when Sam had just died.
I told Berry the idea was morbid. I got chills thinking about it.
There was no way I’d even consider the role.”

It made me extremely nervous to even think about a soul singer who gets shot to death.”