Transcript for Billie Eilish on working with Hans Zimmer on Bond theme song and her rise to stardom
breakout star. Reporter: The song of the year, "Bad guy" by Billie I'm the bad guy Reporter: With almost 800 million view the on YouTube. I literally am living the exact life that I would have a dream about. That would be like the best dream could you possibly think of. Reporter: The 18-year-old pop star has arrived. She's performed live at the oscars and the grammy awards. Reporter: Where she won five awards of her own, becoming the youngest solo artist ever to win album of the year, along with her brother phineas, who is her creative partner and producer. We stand up here confused and grateful. Thank you. Reporter: The two have become one of the hottest teams in music. So what does it feel like when you're winning the biggest awards of the night on your debut album? That we made in his bedroom in our childhood home. It was crazy. Reporter: Now their latest accomplishment, writing the theme song for the next bond movie "No time to die." There ate just no time to die Reporter: Making Billie the youngest artist ever to write the of sound track for the franchise. I don't know if it's going to be good or not, then we got that melody and it was just there, done. Reporter: They collaborated with Hans zimmer who is scoring the rest of the movie. I just loved it from the moment I heard it. Just got under my skin and stayed there. I'm honored to be allowed into that relationship for a moment. You know. I think we did good. Reporter: Billie and phineas have been making together since they were kids. I had time to focus on things I wanted to focus on. Reporter: Detailed in a documentary by apple music the two grew up home schooled in a home of actors and musicians. It allowed them to have this creative life. Reporter: How does one relationship inform the other? Our friendship and siblingship is exactly the same as our professional relationship. We don't really turn on a business switch. I feel a great sense of satisfaction when Billie feels close enough to say, I don't like that at all. Reporter: They caught the ear of industry executives and the pair began releasing songs in 2016. Her breakout track "Ocean eyes" garnered 200 million views on YouTube when she was just 14 years old. Since then, they've become a hit machine, from "You should see me in a crown" to the dreamy "Everything I wanted." Billie's style is as distinctive as her sound, known for pushing the envelope with her avant-garde looks. What goes through your mind when you see that? How long the shoots were. Dude, "Vogue"? I don't know. Life is crazy. This is insane. Reporter: With her career taking off at a whirlwind pace over the last year, it's easy to forget she's still a teenager. I'm 18. My life is so professional. After a certain amount of hours I turn into a teenager. Reporter: Her own idol, Justin Bieber offered support for Billie in an interview with apple music. I just want to protect her, you know? I don't want her to, you know, go do anything I wouldn't do. I don't wish that upon anybody. So, yeah. If she ever needs me, I'm just a call away. Reporter: How did it make you feel to see him speak about new that way? Dude, you can't even imagine. I don't think he understands how big of a deal that is, and, you know, just him breaking down, saying that he wants to protect me is like the craziest thing ever. Reporter: Another childhood dream, writing that 007 theme song. It's literally been something that phineas and I have wanted to do for years. It was always a dream of ours, we always wanted to do it. But I thought maybe in our 30s or 40s. Reporter: That's decades ay, guys. You're young. Exactly. That's what I thought. Fingers crossed, maybe someday. Reporter: The brother and sister joining a pantheon of like Madonna's "Die another day." To Adele's "Sky fall", and Sam Smith's "Writing's on the wall." Those who do it tend to be celebrated for it. Sam Smith and Adele each have won oscars for their title songs for bond. I'm happy for them. Reporter: Do you think there's a chance if all goes well that next year at the oscars you'll be there as a nominee? As long as "Frozen 3" doesn't come out. Hopefully, yeah. I'm excited for next year and I'm just looking forward to my life. Reporter: Honored at the 2020 Brit awards where she performed "No time to die" live for the first time, Billie seemed to address her recent struggle with negative comments on social media. I've felt very hated recently. And when I was on the stage, and I saw you guys all smiling at me. It genuinely made me want to cry. And I want to cry right now. So -- Reporter: All the awards and acclaims still feel surreal to Billie eilish. How are you enjoying the way things turned out. Dude, it feels like I'm in a dream and I'm going to wake up and it will all be over, and I'll still be little pimply, chubby 11-year-old.
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