When “The Young and the Restless” premiered in 1973, it was the lowest-rated serial on daytime television. Today, it celebrates not only its 10,000th episode, but also remains the No. 1-rated soap since 1988.

The secret of the show’s success, like the secrets belonging to the characters, can be found in the past. Forty years ago this month, co-creator William J. Bell delivered to Screen Gems Television (now Sony Pictures Television) a 65-page “bible,” which was a treatment for “Y&R’s” original characters and story projections.

The document also detailed Bell’s philosophy on the particular dynamics and unique appeal of soap-opera storytelling.

“The serial is an escapist form, one in which the viewer can become deeply involved in the lives of some very stimulating and/or provocative people who dare to live a lifestyle that they, the viewers, perhaps secretly envy,” Bell wrote.

“In the first 25 years of the show, my father created a work of art,” says Bradley Bell, exec producer and head writer of “Y&R’s” sister soap, “The Bold and the Beautiful.” “The storytelling, production values and acting on ‘Y&R’ were different from every soap opera on the air. It’s always been thought-provoking, intellectual, fun and romantic. Like a good parent, it’s morality-based and has been a positive force on the lives of our viewers.”

The senior Bell retired as head writer for “Y&R” in 1998 and passed away in 2005, but the sudser has remained at the top because his successors have maintained the “Y&R” brand.

Many canceled soaps over the years have lost viewers because the shows strayed from core characters and relationships that audiences had grown to expect.

“The foundation of ‘Y&R’ has never changed,” says Jeanne Cooper, an Emmy winner for her role of Katherine Chancellor, which she originated in 1974. “Bill Bell weaved characters that could last a lifetime.”

Steve Kent, senior executive vice president of programming at Sony Pictures Television, concurs that Bell’s genius and his characters have provided “Y&R” with a strong foundation.

“Part of our success also comes from being on CBS, which is the only network that has a full slate of daytime programming,” he says.

Five lead writer regimes have charted the course of “Y&R” since Bell’s reign. Maria Arena Bell, Bell’s daughter-in-law, recently concluded a five-year run as the soap’s showrunner.

“Bill’s vision was so clear and strong,” says Bell. “Dynamics between his core characters are still being played out today.”

Veteran serial scribe Josh Griffith is now the head writer. His material starts airing in mid-October.

“Audiences in this genre much prefer the anticipation of a payoff over a surprise out of nowhere,” he says. “That’s one of the many things that Bill was so great at doing.”

“The common denominator (among Bill’s successors) is that they have the same reverential respect for the show,” says actor Peter Bergman, who joined the show in 1989. “I have every reason to be confident in Josh.”

“Y&R” will celebrate its 40th anni next March and, despite the current TV landscape where soaps have lost some of their luster compared to decades past, there are no current plans to scale back.

“There wasn’t room for (17) shows, but the four that remain serve the market well,” says Kent. “Hopefully, we’ve hit some optimum equilibrium for today’s audience. The future is bright.”

Brad Bell credits his family — mother Lee Phillip Bell (Y&R’s co-creator), brother Bill (president, Bell Dramatic Serial Co. and Bell-Phillip Television), sister Lauralee (an actress who recurs on “Y&R”) and sister-in-law Maria (who wrote the 10,000th episode) — as well as “Y&R’s” extended family of long-running actors, producers, directors and crew for keeping the show at the top.

“They make sure that the qualities that have made ‘Y&R’ so singular, addictive and important have remained,” he says. “My father would be thrilled that we’ve reached this number.”

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