The film adaptation of this hit Broadway show solidified the mainstream appeal of both its faux-’50s sound track and its lead actors, John Travolta and Olivia Newton-John. As star-crossed high school sweethearts Danny and Sandy, Travolta and Newton-John surprisingly sing only seven of Grease‘s 24 songs. Still, their tracks — particularly “We Go Together,” “Summer Nights” and “You’re the One That I Want” — were the film’s biggest hits. Newton-John’s rendition of the ballad “Hopelessly Devoted to You” was nominated for an Oscar for Best Song — although it lost to Donna Summer’s “Last Dance,” from the now forgotten disco film Thank God It’s Friday. No matter: the Grease album is still one of the best-selling sound tracks of all time, and a sing-along version of the movie was even re-released in theaters in 2010.