No one from its debut on March 26, 1973 — when it was just 30 minutes long — remains with the show, but Jeanne Cooper arrived six months later and is the longest-tenured cast member in her role as grand dame Katherine Chancellor.
"God knows it's claimed a big part of my life," the 84-year-old actress said, citing good writing and likable characters as reasons for the show's continued success in an era of dwindling daytime audiences, network budget-cutting and the cancellation of other soaps.
"Its foundation was set so well and you had core characters that you could grow and become involved with," Cooper said. "As you got older, they got a year older. Whether you were wealthy or whatever your status is, our show hit the human being."
An influx of new, younger cast members has arrived since last year to stir the pot in Genoa City, Wis.
"It's an important time to start looking toward the future and the next generation," said Angelica McDaniel, senior vice president of daytime for CBS. "We're not going to rest on our laurels because we're No. 1."
Among the newbies is Lamon Archey, who, as Mason Wilder, gets to mix it up with Eric Braeden, now in his 33rd year playing ruthless tycoon Victor Newman.
"I was thrown in with the big dogs," Archey said. "The last thing I wanted to do was mess up my lines or not be on point. He knows what he wants to do. He gets on set and says, 'Let's run this.'"
Angell Conwell plays attorney Leslie Michaelson, who keeps it strictly business with Braeden's character while getting frisky with businessman Neil Winters played by Kristoff St. John.
"It has its intimidating moments, but it forces you to rise to the challenge," said Conwell, who grew up watching the show with her family in South Carolina.
"They want you to do well," Redaric Williams, who plays Conwell's brother Tyler, said about the show's veterans.
Speaking of alpha-male Braeden, he and Nikki Newman, played by Melody Thomas Scott, recently married for the fourth time, giving the couple 27 weddings between them.
Behind the camera, Jill Farren Phelps took over as executive producer last fall after 11 years of overseeing ABC's "General Hospital," which marks its 50th anniversary next month.
"The greatest challenge when I first came in was to respect the history and legacy of this show. We don't make a decision without careful consideration," she said. "The heart of this show are the characters. The soul has always been the storytelling."
In January, Phelps brought in Steve Burton to play war veteran Dylan McAvoy three months after his long run on "General Hospital" had ended in part because he wanted to spend more time with his family in Nashville, Tenn. He commutes to Los Angeles for tapings.
Burton noticed a difference in how soaps are treated at CBS compared to ABC, which cancelled "All My Children" and "One Life to Live."
"'Young and Restless' means as much to CBS as 'CSI' does and that's saying something," he said. "That all starts from the top down."
Although ratings have dipped, there appears little immediate chance that another show will overtake it soon, said Carolyn Hinsey, a veteran chronicler of daytime dramas and author of "Afternoon Delight: Why Soaps Still Matter."
"The average soap today costs about $40 million to produce," she said. "If the network can monetize that with multiple showings, like 'Y&R' did with SOAPnet and CBS.com, then that's a great bang for their buck. There are no more loyal fans than soap fans."
The show is seen daily by an estimated 10 million viewers in such countries as Australia, Canada, France, Romania and South Africa.
McDaniel has been the driving force in keeping the show current by updating the sets, music and wardrobe, while bringing fans closer through video chats, getting the veterans to join their younger cast mates on Twitter, and cross-promoting "Young and Restless" on other CBS daytime shows. The network also airs "The Bold and the Beautiful."
That kind of effort should keep the show going for years to come, Hinsey said.
"ABC was not loyal to its (canceled) soaps, and did not try to monetize them or promote them," she said. "CBS has been very loyal to 'Y&R' and 'B&B,' especially lately. No new show is going to draw the millions of devoted eyeballs daily that 'Y&R' has enjoyed for 40 years."
Head writer Josh Griffin is loath to give away upcoming story lines, but he promises that "we're going to get hotter and sexier and more romantic and suspenseful as the months go by."
Just the thing to while away an afternoon.