 iHeartRadio. Soundtrack. Flashback. John Travolta and Olivia Newton-John. Name a better duo. 1978's Grease had a soundtrack full of hit songs in their own right and a few created just for the film. Like Hopelessly Devoted to You. Hopelessly Devoted to You. For more great movie soundtrack hits, check out Popcorn Radio on the iHeartRadio app.