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Here Is The Lorde-Taylor Swift 'Royals' Duet We've Always Wanted

Lorde & Taylor are back at it during the 1989 World Tour in D.C.

Almost every night on Taylor Swift's 1989 World Tour, the pop singer has been surprising fans with special guests. People were teasing last night's tour stop in Washington, D.C., as the biggest surprise guest yet. And it was Lorde! She joined her bestie onstage Monday night, apparently flying 19 hours for the dynamic duet.

Taylor drew out her appearance, giving fans clues as to whom it may be before she finally brought the New Zealand singer on stage for a "Royals" duet. A day later, she's still reeling from it. And we are too!

Lorde and Taylor go way back. Tay spent her 24th birthday with Ella, and they've been BFFs ever since. It makes sense that she would join the myriad of famous pals Swift has been inviting on tour.

Last weekend, Swift brought out the U.S. Women's Soccer Team along with The Weeknd for the first night in New Jersey. The second night welcomed guests like Nick Jonas and Uzo Aduba. She also continues to bring out her Victoria's Secret model friends, including Karlie Kloss and Martha Hunt.

Who will she bring out next? Well, we have a few guesses...

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