Brotherly love x 4

Nepotism is not unknown in the TV business, but with his latest project, Shaun Cassidy has taken family ties to a new extreme.

Cassidy is the 1970s teen idol who has spent the last 15 years as a television writer-producer of cult dramas with a sci-fi bent (“American Gothic,” “Invasion”). Now he’s turned his attention to musical comedy with ABC Family’s “Ruby & the Rockits,” about two middle-aged brothers, former rock gods who get reacquainted after the long-lost daughter of one of them reenters the picture. The series premieres its 10-episode run tonight.

For the cast, Cassidy stayed close to home -- literally. One of the leads is his half brother, David, who had his own heartthrob stint as the lead singer on “The Partridge Family,” the early ‘70s sitcom about a family of rock singers that “Ruby” deliberately echoes. The other is stage actor Patrick Cassidy, the younger brother whom Shaun freely admits torturing endlessly during childhood (and well beyond, according to Patrick). The clannishness doesn’t stop there: Ryan, the youngest Cassidy brother, works behind the scenes as the show’s lead set dresser. (The title character, David’s 15-year-old daughter, is played by former “Spy Kids” star Alexa Vega.)

Is it all too twistedly self-referential? As the writer in the family, Shaun Cassidy is aware of the dangers.

“The double-edged sword of working with family is it can be the most fulfilling experience you’ve ever had,” Cassidy, 50, said during a recent interview in his office on the CBS lot in Studio City, where “Ruby” is filmed. “But the flip side is it can also be the most tortuous and most stressful, because it’s your family and the lines can get blurry.

The brothers are all sons of Jack Cassidy, the prolific comic actor whose presence continues to hang over the family nearly 33 years after his death. David is the son of Cassidy and Evelyn Ward; Jack Cassidy later married actress Shirley Jones, the mother of Shaun, Patrick and Ryan. In a paradoxical twist, she played David’s birth mother on “The Partridge Family.”

When a visitor entered a soundstage where the “Ruby” cast was rehearsing, the four brothers were chuckling over an old photo of their father. It showed Jack Cassidy in costume for “He & She,” a 1967-68 CBS sitcom in which he played a preening, hyperconfident actor. In a coincidence that almost seemed preordained, the Cassidy brothers are now toiling on the very same studio lot where “He & She” was shot more than four decades ago.

According to Shaun, his father’s personality, on-screen and off, inspired the character of David Gallagher, the narcissistic performer whom David Cassidy plays on “Ruby.” (“It’s just who he is. It’s very larger than life,” Patrick, 47, says of David’s character on the show. “Everything is extreme.”)

Even today, his sons seem to wrestle with ambivalent feelings toward their father. David has described Jack in interviews as an alcoholic, a sufferer of bipolar disorder and a closet bisexual who broke his heart by abandoning him when he was young.

But for this story, David, who at 59 has thinner hair but is nearly as lean as during his pop-idol days, offered a balancing perspective: “If you put all my brothers together, we would add up to all the talent that was in my father.”

The burden of spinning laughter out of this tangled family history fell to Shaun. The key, he realized early, was to satirize the pop-music stardom he learned in his first brush with fame during the days of white disco suits and shag hairdos.

He remembers being flown to a gig in Hawaii at age 19 and seeing thousands of fans spelling out his name with their bodies on Waikiki Beach. It was a surreal experience, he says: “I was sort of in it, but not of it. It was all out-of-body for me.”

This phase of his life is never far away, even three decades later.

During the interview, Marsh McCall, who helps wrangle the “Ruby” writing staff, barged in with a Shaun Cassidy action figure, still in its original packaging. McCall joked that the doll could be sold on EBay, because, as he told Cassidy, “I know you need the cash.”

Cassidy found more fame on ABC’s “The Hardy Boys/Nancy Drew Mysteries,” then spent much of the 1980s in the theater. But by the time he costarred with David in the Broadway hit “Blood Brothers” during the early 1990s, Shaun had tired of performing. His writing and producing career got an early boost in 1995, when CBS picked up “American Gothic,” the satirical sci-fi series he made with director Sam Raimi. The show retains a cult fan base even though it ran just one season. During the 2005-06 season, ABC aired his alien-takeover series, “Invasion.”

With “Ruby,” Shaun saw a way for the family to work together in a project that would recall another Cassidy opus. “He said, ‘I kind of wanna do a new “Partridge Family,” ’ “ said Kate Juergens, head of programming for ABC Family.

The premise has David and Patrick Gallagher, hit-making brothers behind the ‘80s group the Rockits, finding their lives upturned after David’s daughter Ruby reenters the picture. Patrick has settled down and became a car dealer and family man; David is still playing small casinos and chasing a comeback.

Asked if he’ll find a part for his mother, the 75-year-old former “Partridge Family” matriarch, Shaun replies: “We haven’t written her in yet, but it’s coming. She comes to every taping.”

To help lure the teen girls who form ABC Family’s base, the cast includes Austin Butler, late of Nickelodeon’s “Zoey 101,” as Patrick’s son, an aspiring singer-songwriter.

David, for one, was immediately enthusiastic about the prospects.

“I told [Shaun] from Day One when we started talking about it, I said, ‘I know you’re going to think I’m insane, but I’m telling you, we’re going on the air with this.’ And of course Shaun looked at me like,” he rolls his eyes, “ ‘We haven’t even pitched the idea.’ ”

Shaun is trying hard to keep a critical perspective on the family’s latest business.

“It’s not about a famous family,” he said of the fictionalized Gallagher clan. “It’s about a real family that happens to have music and some show business just in the wallpaper. It’s just part of the fabric of the environment. Which, again, is how we grew up.”

--

scott.collins@latimes.com