Jack Black surprises Broadway's 'School Of Rock' cast

The cast of Broadway musical 'School of Rock' was left in awe after Jack Black surprised them backstage. The 46-year-old actor starred as the school teacher and rock wannabe in the hit 2003 film on which the production is based, and Black was able to watch the show for the first time, along with his son and actor Paul Rudd, reported Contactmusic.

I have a private side: Jack Black


Following the matinee, the actor met the cast and crew, including Alex Brightman, who plays Jack's character in the musical, and he took to Instagram to post several photos with the star. "I'm losing my mind. He was the greatest guy. And he had the nicest things to say about @sormusical. Thanks for coming, Mr. Black... He is cooler than you even think he is," Alex said.

WATCH: Jack Black | Getting Doug with High