India, June 29 -- Actor John Travolta attended a Grease sing-along at the Hollywood Bowl in Los Angeles on Friday, June 27. The actor shared a glimpse of his surprise appearance, in which he was dressed as his iconic character, Danny Zuko. He also revealed that the cast didn't know about it.

On Saturday, John took to Instagram and shared a photo of himself as an older version of Danny Zuko, along with a video of his surprise appearance at Friday night's Grease sing-along event in Los Angeles. The video showed the crowd rising from their seats, clapping and cheering as John joined the other cast members on stage. John, 71, channelled Zuko and said, "L.A., I thought you were going back to Australia? That's cool, that's cool, baby. You know...