VIDEO: John Travolta and Olivia Newton-John Talk Timelessness of GREASE at 40th Anniversary Celebration

Grease is still electrifyin' audiences 40 years later and the film's original stars, John Travolta and Olivia Newton-John reunited for at special anniversary screening at the Samuel Goldwyn Theater in Beverly Hills on Wednesday night.

The pair talked about how Grease is timeless.

"I like to keep it a mystery because I don't really know the reason," Travolta said. "But I'm just glad it is."

Travolta and Newton-John spoke on a panel alongside other original cast members from the film. The panel was moderated by Mario Lopez, who played Vince Fontaine in Grease Live! on Fox.

The cast discussed how Grease has been with them for decades, and the impact the film had on all of their lives.

Watch the full panel below, as well as clips of the stars on the red carpet!

Featuring an explosion of song and dance, as well as star-making performances from John Travolta and Olivia Newton-John, GREASE made an indelible impact on popular culture. 40 years later, the film remains an enduring favorite as legions of new fans discover the memorable moments, sensational soundtrack and classic love story. Boasting unforgettable songs including "Greased Lightnin," "Look At Me, I'm Sandra Dee," "Summer Nights," "Hopelessly Devoted To You," "Beauty School Drop Out" and, of course, "Grease," the film is a timeless feel-good celebration.