Julia Roberts and Stephen Colbert.

The Oscar winner recently appeared as a guest on ‘The Late Show With Stephen Colbert.’

Stephen Colbert asked Julia Roberts that very question during her latest guest appearance on CBS’ The Late Show, and her answer did not disappoint — especially not the Emmy-winning host, 61.

Depending on the person, it might be hard to remember details about one’s first live-music experience — but not for Roberts, 58.

“My mom thought I was at Donna Walter’s house studying,” the Oscar winner tells Colbert in the episode that aired Monday Nov. 17, after confirming that she was able to see Rick Nielsen and company perform after sneaking out.

But then the truth comes as to why the late-night host seemed so astonished when Roberts named Cheap Trick in particular as her first concert: Nielsen, 76, wrote the theme song to Colbert’s beloved show, The Colbert Report.

Julia Roberts Warns Stephen Colbert 'You Won't Last Past May'

And why the Cheap Trick frontman? Colbert explains to Roberts that he had reasoned with Nielsen at the time that his fictional “Stephen Colbert” who hosted The Colbert Report would probably have sung the iconic band’s “I Want You to Want Me” to himself before he’d go out on stage for each show. So why not have Cheap Trick’s songwriter scribe the comedy show’s theme song?

It’s clear then, that a funny little connection in the form of Cheap Trick was drawn inadvertently between Roberts and Colbert’s throwback alter ego on The Late Show. See the clip below.

Roberts has been busy promoting her new movie After the Hunt this fall, a psychological drama/thriller that also stars Andrew Garfield. When the movie premiered at the BFI London Film Festival last month, the Golden Globe winner 42, revealed what it was like working with Roberts and shared an unexpected detail about her.

“She’s like an iconic movie star that also happens to be the coziest human being you could spend time with,” Garfield said. “Great chef, and the banana bread is unparalleled.”