Billy Joel is detailing his complicated relationship with his dad in his new documentary 'And So It Goes,' including the time his father 'knocked me out' as a child for playing 'Moonlight Sonata' incorrectly.

Take a look back at Joel's former partners, including Christie Brinkley, and get to know his current wife, Alexis Roderick Joel, too.

At one point, [Billy] said to me, 'You going deep?' And I said, ‘Yeah, and you know you’re going to go deep too,'" the film’s co-director Susan Lacy says.

Billy Joel introduced himself to the Billboard Hot 100 with the eventual classic, and one of his signature songs, "Piano Man," which hit No. 25 in April 1974. He landed his first No. 1 in July 1980 with the celebratory "It's Still Rock and Roll to Me.

The "Piano Man" singer is set to appear on the 'Club Random' podcast next week, with a video clip from the interview released on Friday.

Alexa Ray Joel watched the new documentary about her father, 'Billy Joel: And So It Goes,' with mom Christie Brinkley. The film premieres in two parts on July 18 and July 25, on HBO Max.

Billy Joel is opening up about one of the most complicated chapters of his life in his new documentary, "Billy Joel: And So It Goes."