In an exclusive clip provided to ET from the audiobook of her memoir, Don't Stop Believin', Newton-John fondly recalls her Grease screen test with John Travolta on the Paramount lot in Los Angeles.
"When we walked inside the room together, it was magic, and everyone saw it, knew it," she said. "They couldn't deny this kind of chemistry. We were right next to each other, up close and personal -- Sandy and Danny standing there in the flesh. The best part? We hadn't even read one line."
The book and audiobook of Newton-John's autobiography are out Tuesday from publisher Simon & Schuster.
Newton-John, 70, recently revealed that she is battling cancer for a third time. In an interview on Monday with ET'sNancy O'Dell, Newton-John shared the secret to her resilience. "Every day is a gift, anyway, we don't really know how long our life is," she said. "I'm very grateful. I intend to be here for a long time. I have so much to do still. I'm enjoying my life."