John Travolta, who starred as 'Grease' bad boy heartthrob Danny Zuko, crashed the Hollywood Bowl's sing-along event Friday.

John Travolta pulled out the hair gel and leather to revive his role as Danny Zucco in a Hollywood Bowl screening of "Grease.

Screen icon John Travolta made a surprise appearance at a "Grease" sing-a-long at the Hollywood Bowl this weekend.

Fans at the 'Grease' Sing-A-Long screening at the Hollywood Bowl last night got a surprise when the original Danny Zuko ...

You never know what’s going to happen on those summer nights at the Hollywood Bowl. On Friday night, the iconic venue hosted ...

John Travolta made a surprise appearance at Friday night’s “Grease” sing-a-long at the Hollywood Bowl dressed as his iconic ...

The clip showed the “Pulp Fiction” alum walking out as the crowd went wild before Travolta joined his stunned “Grease” ...

John Travolta gave "Grease" fans the thrill of their lives when he dressed up as Danny Zuko for a surprise appearance at a ...

John Travolta made a surprise appearance at Friday night’s “Grease” sing-a-long at the Hollywood Bowl dressed as his iconic ...

John Travolta surprised fans at the Hollywood Bowl Grease sing-along, reprising his iconic Danny Zuko role with a stylish ...

John Travolta is tapping into our nostalgia. The actor, 71, made a surprise appearance at Friday’s “Grease” sing-a-long at ...