If you have watched the Netflix hit series "The Crown," you may remember its opening credits. It’s visually riveting, as we see tendrils of liquid gold solidifying and forming parts of a crown. The mood is bolstered by a captivating melody that builds into a grand overture.

That music is the work of composers Hans Zimmer, Lorne Balfe and Rupert Gregson-Williams. Gregson-Williams has scored a lot of Hollywood blockbusters such as "The Legend of Tarzan," "Hacksaw Ridge" and "Wonder Woman," but for "The Crown," Gregson-Williams went for a haunting sound, as heard in the opening credits’ theme. It’s inspired by a remarkably daring aria by 17th century English composer Henry Purcell, “What Power Art Thou.” 

Gregson-Williams says he and his fellow composers brainstormed intensely about how to shape this theme after series creator Peter Morgan gave precise instructions about evoking the drama of postwar Britain. 

“Peter Morgan was very specific about how he wanted to feel like we had tectonic plates shifting in the world,” he says. “He wanted it to feel regal, but without being pompous, and we had lots of conversations. In fact, that theme took quite a long time, a lot of time talking and not writing, and eventually we got it.”

Season One of "The Crown" focused on the birth of a queen, a young woman stepping into a demanding role, with apprehension. In an early scene, we see Elizabeth II, played by Claire Foy, trying to walk with her heavy crown.

The music in the first season conveys a sense of awe and wonder. But Season Two hits a darker tone, reflected in a bigger and more menacing orchestral sound. Co-composer Lorne Balfe says that’s because the characters have matured. 

“The queen is now a reigning monarch instead of a young girl given this position,” Balfe says. “It’s a different journey for them and that’s why the music evolves.” 

Queen Elizabeth is dealing with an increasingly strained marriage, scandals that threaten the monarchy and headlines that call her out-of-touch. And international events rock the country: The Suez Canal Crisis, for example, which leads to the resignation of Prime Minister Anthony Eden.

Netflix says this second season “bears witness to the end of the age of deference and ushers in the revolutionary era of the 1960s.” In this story, much of that sentiment is carried by Princess Margaret. “I know who I am: a woman for the modern age, free to live, to love, free to break away,” claims her character.

Gregson-Williams says as far as he could tell, Princess Margaret stood apart from the rest of her family. “She was just a completely different animal and always trying to break out of the mold of the royal family,” he says. “And that’s where the difference is, Elizabeth still living in pre-war times and Margaret trying to be something a little bit more modern.”

Composer Lorne Balfe says the soundtrack only exists to support the dialogue. But in this series that paints intimate portraits of royalty and chronicles major events of the 20th century, the music is as stirring as the story.

Season Two of "The Crown" and the soundtrack are out Dec. 8. 

From PRI's The World ©2017 PRI