When Katy Perry released the era-defining 2010 album Teenage Dream, she became the biggest pop star in the world—by a long shot. It spawned a record-breaking stretch of No. 1 hits, a documentary by Paramount Pictures, cameos on SNL, stadium-level world tours, lines of perfume, shoes, and makeup, and a glitter-bomb halftime show in which she rode a shooting star. But in her latest interview with Zane Lowe, she opens up about what happened when all that slipped away. “I used to be able to fix my depression by going, ‘I'm going to write a freaking song. You break up with me? I'll show you. Here's a No. 1.’ But then it didn't work anymore and everything changed. The world didn't want to hear from me anymore. And I couldn't get out of bed for weeks and became clinically depressed and was so ashamed of it. I was like, 'I'm Katy Perry. I wrote "Firework." This is f**ked up.” Here, the superstar—engaged and 35 weeks pregnant—describes the pain, perseverance, and self-care that shape her triumphant sixth album Smile.