America fell in love with John Travolta and Olivia Newton-John in 1978 when the pair played the roles of playboy Danny Zuko and naive exchange student Sandy Olsson in the iconic musical Grease.
Despite their electrifying chemistry, that was the first and only time that Travolta and Newton-John have appeared in a film together.
Travolta went on to star in a number of critically-acclaimed and award-winning films, including Pulp Fiction, Hairspray and Get Shorty. Newton-John also took up numerous acting gigs, but she had more success with her music career. She had a string of number one hits and won four Grammy Awards.
Still, the on-screen couple remained good friends all these years.
"John and I have stayed in touch, and in 2012 we made a Christmas album and sang a duet called "I Think You Might Like It," which was a sort of sequel to "You’re the One That I Want" by the same writer, John Farrar," Newton-John told The Telegraph last year.
She also commented on her friendship with Travolta in another interview a few years prior.
"Friendships like that are to be treasured because it’s rare to find it once in a working lifetime. I found it twice, with Cliff [Richards] and John Travolta," Newton-John said in an interview a few years ago.
Over the years, the pair have had a couple of mini reunions - from appearing on The Ellen DeGeneres Show to performing an impromptu duet on stage during Newton-John's tour.
This week, Travolta and Newton-John have once again proved that they're hopelessly devoted to each other as they enjoyed another mini reunion at an event in Los Angeles.