"The Defiant Ones" chronicles the powerful partnership of Jimmy Iovine and Dr. Dre

HBO's new docuseries, "The Defiant Ones," begins with a multibillion-dollar deal in jeopardy.

Apple's planned purchase of Beats by Dre had been leaked to the press, throwing long-time partners and founders of the headphone company, Jimmy Iovine and Dr. Dre, into total crisis.

The partnership of that unlikely duo—a record executive and a rapper from Compton—runs deep. It had begun 25 years prior when Iovine's Interscope Records acquired the rights to market and distribute Dr. Dre's work with Death Row records.

"The Defiant Ones," directed by Allen Hughes, chronicles their storied relationship through interviews with artists and music executives they've worked with over the past few decades.

Hughes and Iovine joined "CBS This Morning" to talk about the powerful relationship explored in the four-part series.  

Hughes was determined to let audiences know immediately that this was not going to be a "fluff piece" or a "tribute film." That's why he chose to begin with Iovine and Dr. Dre at one of their worst moments.

"This is going to be a serious film—the good, the bad and the ugly," Hughes said.

Despite being from seemingly different worlds, the two partners had some important things in common.

"Dre's from Compton, I'm from Brooklyn and we both wanted to make a better life for ourselves, right. And we both—somehow we're both recording engineers that's how we got our break," Iovine said.

Ironically, for a docuseries that centers on their relationship, the two don't actually meet until the third episode.

"It shows the strength of their partnership," Hughes said of that decision.

"We stuck together in some of the most difficult and unnerving times ever in the history of the entertainment business," Iovine said.

Even friends of Iovine have questioned how the two stuck together for so long.

"Because I believe in him and he stayed with me," Iovine said. "The thing was that he trusted me and there was no basis for him to trust me."  

Iovine is known for his tough opinions; in the film, U2's Bono calls his honesty "brutal."

Prompted for a sample of the kind of brutal honesty he's served up to Bono, Iovine said, "He'll come to me and say, 'It's the greatest song I ever wrote,' and I say, 'Well, no it's not.'"

Another important moment of honesty? When Dre was approached to do a sneaker deal, Iovine told him, "Don't do sneakers—do speakers."