Jack Black was walking around Cathedral Square in Christchurch, NZ the day before his band Tenacious D was set to play. That’s when he noticed a pair of 10-year-old buskers playing a rocking version of Bob Dylan’s ‘All Along The Watchtower.’ But he didn’t just give them money– Black offered them the opening slot in his show.

Watch a rock-and-roll fantasy become reality for a burgeoning band of kids named Black Tear.

The clip is from Jeremy Konner’s documentary ‘D Tour: A Tenacious Documentary.’ And yes, the special handshake Black does with one of the Black Tear members is from the movie ‘School of Rock.’

But there is no better “School of Rock” than what the boys were exposed to that night, and you can see it in the smiles on their faces when they perform for the large crowd. As a result of the show, three record labels contacted Black Tear.

It’s a pretty touching video all around, but it will have particular resonance for residents of Christchurch, who get a peek at what their city looked like before being badly damaged in a 2011 earthquake.