Robert Reed, known as the lovable, wholesome dad from "The Brady Bunch," wasn’t eager to play second fiddle to a young John Travolta.

That claim was made by Joel Thurm in his book titled "Sex, Drugs & Pilot Season: Confessions of a Casting Director," where he dished on his time in Hollywood. In it, he detailed the making of the 1976 drama "The Boy in the Plastic Bubble," which starred both Reed and Travolta.

"That film was a labor of love for everybody except Robert Reed," Thurm claimed to Fox News Digital. "For him, it was just a paycheck. He just couldn’t deal with the fact that our short schedule completely revolved around John. The thing is, we just had 17 days to work with John before he had to go back to shooting ‘Welcome Back, Kotter.’ That made it inconvenient for everybody else, but we all understood, and it was totally fine. That’s just what we had to do. But not for Robert Reed."

Joel Thurm's book cover

Joel Thurm recently wrote the tell-all book, "Sex Drugs & Pilot Season: Confessions of a Casting Director." (BearManor Media)

"He was really a p---- on the set," Thurm alleged. "He was there for one reason. He was there for a paycheck."

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"The Boy in the Plastic Bubble," a made-for-TV drama, told the tale of a teen born with immune deficiencies (Travolta) who yearns to leave his germ-free bubble all thanks to the girl next door (Glynnis O’Connor).

In the book, Thurm described Travolta as "a kid" who was "having a ball and very friendly to all members of the cast and crew." It was at a time when the actor was skyrocketing to fame and "couldn’t go anywhere without getting mobbed." As for Reed, Thurm alleged he "was the only annoyance" on the set "who turned out to be a royal pain in the ass."

Side by side photo of Robert Reed and John Travolta

Joel Thurm alleged that Robert Reed, left, who worked alongside John Travolta in "The Boy in the Plastic Bubble," made his annoyance known on set. (Getty Images)

"Understandably, ‘The Brady Bunch’ had pumped up his ego, and Reed was used to being as important as anyone on the set," Thurm wrote. "But in ‘Bubble,’ he was neither the star nor the center of attention. The shooting schedule depended on John finishing his scenes in the 17 days he was available. All scheduling had to be worked around this. Reed couldn’t handle the demotion. He was sulky, curt and made it all too clear that this job was just a paycheck to him."

Thurm said Reed’s annoyance came to a head – "literally" – on the day when his curly hair had to be straightened and rekinked twice. The laborious task was meant to show his character’s changes in appearance over the years.

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"It was a lot of time for him to be on the chair," said Thurm. "And he was miserable – just miserable. And what happened, happened."

Robert Reed smiling against a red backdrop

Robert Reed is recognized by many as patriarch Mike Brady in "The Brady Bunch." (ABC Photo Archives/Disney General Entertainment Content via Getty Images)

In the book, Thurm said he went over to Reed’s dressing room in an attempt to smooth things over. That’s when things allegedly took a turn.

"Reed wound up storming into his dressing room, which, by the way, was equal in all respects to John’s," Thurm wrote. "I followed him and apologized, trying to explain, once again, our ridiculous schedule."

Thurm alleged he offered the grumpy star a back rub – one that turned into more.

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John Travolta in a scene from 'The Boy in the Plastic Bubble'

Tod Lubitch (played by John Travolta) was born with a deficient immune system that forced him to spend his life in a completely sterile environment. (ABC Photo Archives/Disney General Entertainment Content via Getty Images)

"The deed that should not have been done got done," Thurm alleged. "I did leave him in a better mood, but Reed, who was professionally closeted, never looked me in the eye for the remaining few days of shooting and returned to being a pain in the ass… As promised, we finished with John within his 17-day limit."

In the book, Thurm also alleged that he had a less-than-memorable sexual encounter with another closeted actor – Rock Hudson.

"You mean my non-encounter," Thurm clarified. "The important thing is that nothing happened. That’s the reason why the story is funny."

a black and white photo of Rock Hudson from 1982

Joel Thurm detailed his alleged first meeting with Rock Hudson, whom he described as his teen idol, in his book. (Getty Images)

Thurm alleged that in the ‘70s, he attended an industry party where most of the attendees were gay and "lots of liquor was poured." In attendance was his teen idol. He claimed that the "Giant" star caught his eye and made a "follow me" motion to the bedroom upstairs. Thurm insisted that he was "so anxious and nervous" that nothing more occurred – to his embarrassment.

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Thankfully, he said, Hudson forgot all about it and appeared unfazed as he was gearing up for his latest project.

"It would be years later, probably 10 years later, until I saw him again at my office," said Thurm. "We were casting a cop series called ‘The Devlin Connection’ and he was there. Fortunately, he had no idea who I was, which was just fine with me!"

Rock Hudson in the drivers seat of a car in a scene from the television series 'The Devlin Connection'

Rock Hudson starred in the short-lived series "The Devlin Connection" in 1982. The actor passed away in 1985 at age 59. (Mammoth Films/Getty Images)

Hudson passed away in 1985 at age 59 from complications of AIDS. Reed later died in 1992 at age 59. His death certificate indicated he was infected with HIV. In their lifetimes, both men kept their sexuality a secret, knowing it would have derailed their thriving careers.

Over the years, Thurm was involved with several iconic TV shows and films, such as "Rocky Horror Picture Show," "The Golden Girls," "Family Ties" and "Miami Vice." He’s also met numerous stars on the rise along the way. But it was Travolta, who Thurm met when the actor was just 17 years old, that left a lasting impression on him.

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"I remembered when he walked into my office in New York – this was before anything," Thurm recalled. "He was just a polite, charming and incredibly handsome young man - he was a star right from the beginning. Even though he was from New Jersey and his name ends in a vowel, he was nothing like the character he would play, Vinnie Barbarino, in ‘Welcome Back, Kotter.’ John Travolta was just one of those people you met and instantly knew he was special, that he was going places."

John Travolta looking serious against a red backdrop

Joel Thurm said he instantly knew that John Travolta was going to be a star in Hollywood. (ABC Photo Archives/Disney General Entertainment Content via Getty Images)

"In that meeting, we talked about his aspirations," Thurm shared. "He told me that he really wanted to learn how to fly an airplane. It was just a wonderful meeting with this young man with dreams and ambitions. But it was only when he moved to California that things really began to move for him. And I wasn’t surprised. He had that star quality from the start."

While "The Boy in the Plastic Bubble" didn’t result in an Emmy nomination for Travolta, Thurm said it led to something much more important. It showed audiences and filmmakers that Travolta could act beyond sitcoms. After that film, Thurm and Travolta worked together in "Grease" and "Moment by Moment."

John Travolta in a scene from The Boy in the Plastic Bubble

After 1976's "The Boy in the Plastic Bubble," John Travolta went on to star in 1977's "Saturday Night Fever" and 1978's "Grease." (ABC Photo Archives/Disney General Entertainment Content via Getty Images)

"What I hope readers get from my book – and it starts at the very beginning – nobody knows anything about how the casting process works," said Thurm. "Casting directors don’t choose the people who wind up with the parts. We suggest, cajole, hammer over the head, twist arms, and do anything that we can to convince the people who make the decisions. But we certainly don’t have the last word."