“I felt like I was doing the best work of my life on some of these shows,” she said. “It was so frustrating.”

Last year, Peter Roth, the president of the Warner Bros. television unit, asked Ms. English to consider writing a “Murphy Brown” script after the speechwriter idea did not sell. Mr. Roth saw that the TV landscape was being inundated with revivals, and many were doing quite well in the ratings.

Ms. English reached out to her original cast to see if they were game. It turns out, several of them were all but done with show business.

Mr. Shaud, who played Miles, said he had moved to a “compound in Pennsylvania.” Ms. Ford, who played Corky, had left Los Angeles in 2012 and relocated to Louisiana, while still doing the occasional TV movie. Mr. Regalbuto, who played Frank, said he was in his pajamas when he got the email from Ms. English. It was around 6 in the evening.

“We were all have been blessed to have been on this show, blessed to have good careers and done stuff,” Mr. Regalbuto said. “But personally, I was thinking: Should I take my pension?”

All of them agreed to return.

Ms. Bergen was also intrigued by the idea of returning but she had one condition: The show would need to be shot in New York, so she could stay close to her husband, Marshall Rose, who is not in any condition to travel, she said.