The real reason Olivia Newton-John and John Travolta never dated exposed in new biography

“Grease” co-stars Olivia Newton-John and John Travolta would have dated if it weren’t for the actor’s devotion to Scientology, according to a new biography about the late singer.

In his book “A Little More Love: The Life and Legacy of Olivia Newton-John,” writer Matthew Hild shares a conversation the Australian icon reportedly shared with a musician who joined her band and who had been married to a Scientologist.

“I know the Church of Scientology really reveres [Travolta] as a very valuable follower,” Newton-John began, per an excerpt of the biography obtained by People ahead of its Thursday release. “If I had married John, would he have expected me to become a Scientologist?”

The bandmate – who described the “Grease” co-stars as “very, very close” and “almost that close” – reportedly told Newton-John that it “would not have been mandatory” for her to convert, but it “would have been encouraged.”

“Thank you,” the “I Honestly Love You” singer replied, per Hild’s book. “That’s all I want to know.”

Newton-John and Travolta first met during a screen test for “Grease” shortly before it started filming in the summer of 1977.

The “If Not For You” hitmaker played the sweet-natured Sandy Olsson in the iconic 1978 musical rom-com opposite Travolta’s leather-clad Danny Zuko.

Although the pair shared undeniable chemistry in their respective roles, Newton-John explained why they didn’t date behind the scenes of “Grease” during a 2018 interview.

“We were both with other people when we were filming and I think, respectfully, it just didn’t happen,” she explained during the “No Filter” podcast four years before her death.

“I think it was good, because I think it kept the tension there and the chemistry. It might have been a real disaster had we decided to date or we had a falling out or something,” Newton-John added. “So I think it was just as well that it didn’t happen.”

Still, Newton-John and Travolta remained good friends and reunited on the big screen for 1983’s “Two of a Kind.”

Meanwhile, the “Physical” singer went on to marry actor Matt Lattanzi in 1984. The pair welcomed a daughter, Chloe, before divorcing in 1995.

Newton-John then remarried and tied the knot with businessman John Easterling in 2008 after a lengthy on-again, off-again relationship with cameraman Patrick McDermott. She and Easterling were still married at the time of her 2022 death.

As for Travolta, the 72-year-old “Pulp Fiction” star married actress Kelly Preston in 1991.

The couple welcomed three children together before Preston died in 2020 at the age of 57 following a private two-year battle with breast cancer.

In 2022, after Newton-John’s death from breast cancer at the age of 73, Travolta shared a sweet tribute to his former co-star via Instagram.

“My dearest Olivia, you made all of our lives so much better,” he wrote. “Your impact was incredible. I love you so much. We will see you down the road and we will all be together again.”

Travolta added, “Yours from the first moment I saw you and forever! Your Danny, your John!”

The “Saturday Night Fever” star remembered Newton-John once again with a touching tribute during the In Memoriam segment at the 2023 Academy Awards.