“She was incredible. She was just as lovely on the inside as she was on the outside and what people don't know, which is why you're probably talking to me, is she initially was not interested in 'Grease’,” he revealed.
“She had been embarrassed by a movie she had made earlier before she became a huge star here and didn't want to repeat that experience.”
The movie Thurm was referring to was the 1970 flop Toomorrow, a film plagued by pre- and post-production issues that premiered to very tepid response and was ultimately shelved after just a week in theatres.
“Our film died a death and it was all a bit of a shambles. But it was a good experience,” Newton-John told NME in 1971.
The experience led to an eight-year film hiatus for Newton-John, who remained hesitant during the casting process for Grease.
Funnily enough, that hesitance extended to the man who had been pegged to play the male lead, John Travolta.
“So she asked for a screen test so that she could see herself and John and decide whether she wanted to do the movie or not,” Thurm explained.
And it didn’t get off to a promising start:
“We did the (screen test) scene in the drive-in. The first couple of takes with John, the full screen test, didn't work because they were reading the dialogue from the movie script. No laughter after three or four takes.
“Then I figured out what was wrong and I pulled out the script from the original musical. Same scene, different dialogue. I gave that to the director and to John and Olivia and the next take, the crew was laughing. Second take, the crew was laughing…
“After that, when she saw that tape, she was in. She did not jump up and down and take the initial offer. She was a very, very, very smart woman in addition to being a very talented one.”
Today hosts Karl Stefanovic and Ally Langdon were surprised by the revelation in studio.
“What an incredible story. Sandy and Danny were almost never together on 'Grease'. It almost didn't work with Olivia Newton-John and John Travolta!” they exclaimed.
Newton-John died in the early hours of Monday morning (local time) at her ranch in Southern California.
Her husband, John Easterling, confirmed the news in a post to social media, saying that Olivia was "a symbol of triumphs and hope".
"Dame Olivia Newton-John (73) passed away peacefully at her Ranch in Southern California this morning, surrounded by family and friends. We ask that everyone please respect the family's privacy during this very difficult time," Olivia's husband wrote.
"Olivia has been a symbol of triumphs and hope for over 30 years sharing her journey with breast cancer.
"Her healing inspiration and pioneering experience with plant medicine continues with the Olivia Newton-John Foundation Fund, dedicated to researching plant medicine and cancer.
"In lieu of flowers, the family asks that any donations be made in her memory to the @onjfoundation."
Olivia also leaves behind her 34-year-old daughter Chloe Lattanzi.
We're supporting the Olivia Newton-John Foundation by giving them 100% of the profits from the sales of this fabulous ONJ tribute tee. Get yours here.