The Hollywood Bowl’s Grease sing-a-long event was automatic, systematic, hydromatic and grease lightning — thanks to a very special cameo from film star John Travolta.

“Tonight at the Hollywood Bowl, for the first time I surprised everyone at the GREASE Sing-A-Long and dressed up as Danny Zuko,” Travolta, 71, wrote via Instagram on Friday, June 27. “No one knew. Not even the cast. Thank you for a great evening.”

To get into character, Travolta wore a black T-shirt underneath a matching leather jacket with a pair of tight-fitting dark jeans. He also wore a blond wig, styled like Danny’s famous pompadour. (Of course, Travolta’s Danny famously had jet-black locks in the film adaptation.)

“That’s cool, that’s cool,” Travolta quipped on the stage, quoting Danny’s nonchalant comments to Sandy (Olivia Newton-John) after finding out she moved to town. “You know, [I’m] rocking and rolling.”

Grease is the word! When Grease hit theaters in June 1978, it was an instant hit — and its cast members became instant stars. Based on the 1971 musical of the same name, the film follows students at Rydell High School after they return from summer break in 1958. As memorably recapped in the song […]

Travolta was joined onstage by the rest of the OG T-Birds.

“Are you ready to [sing] together?” he asked, leading the audience in the “We Go Together” chant. “Shoo-wop-sha-whada-whadda-yippidy boom-da-boom. Enjoy the show, we love you!”

Travolta starred in 1978’s Grease as Danny Zuko, a greaser who learns his summer fling, Sandy Olsen, moved to town from Australia for her senior year of high school. The catch? Danny never told goody-two-shoes Sandy about his less-than-angelic clique.

“I really had the thought, ‘One day when they do the movie, maybe I’ll get to play Danny,’” Travolta recalled to Yahoo! Entertainment in 2019, noting he was first drawn in by the stage show. “I knew that character like the back of my hand. I knew what worked, and I knew what didn’t work.”

He added, “I knew what was funny, and I knew what wasn’t funny. I knew what was cool looking, in movies. I knew how to comb my hair, how to pose and how to be cool, because all I could do as the other character [Doody] was watch the coolest character — which was Danny — for over a year.”

After starring in Grease, Travolta and Newton-John stayed close until her death in 2022. The actress died that August at the age of 73.

“My dearest Olivia, you made all of our lives so much better,” Travolta wrote via Instagram at the time. “Your impact was incredible. I love you so much. We will see you down the road and we will all be together again. Yours from the first moment I saw you and forever! Your Danny, your John!”