Taylor Swift was performing on Halloween, but don't worry: She still got to wear a costume.
The megastar closed the U.S. leg of her "1989" tour Saturday night and, in something that should shock no one who has been following the tour, brought along a special guest for the Tampla, Fla., show. Idina Menzel, who voiced Elsa in "Frozen," joined Swift to sing "Let It Go" from the Disney hit.
If that wasn't all, the two were in full costume. Menzel donned a sparkly blue dress to look like the ice queen she voiced, and Swift was decked out in full Olaf costume.
"Frozen totally happened tonight," Swift wrote on Instagram that night. "And 55,000 people sang 'Let It Go' so loudly, it nearly took my breath away."
Swift and Menzel shed their costumes halfway through the performance, going for more concert-fitting outfits.
"Thank you Taylor Swift!," Menzel wrote on her Facebook page. "That was definitely an out of body experience. Or out of Elsa's body experience!"
Swift also welcomed another special guest to the stage that night: Alessia Cara, who covered Swift's "Bad Blood" on BBC Radio and impressed Swift so much that the pop star tweeted about it. Cara performed her hit "Here" in front of the massive crowd.
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