A Costumed Taylor Swift Brought Idina Menzel Onstage for a Frozen Singalong

No one is ready to let Frozen go, especially Taylor Swift. The pop megastar was performing the last leg of her extensive U.S. tour on Halloween night in Tampa Bay, Fla., and decided to spruce things up by inviting Idina Menzelonstage for a dual superstar rendition of the Disney movie's hit "Let It Go."

And since it was Halloween, Swift suited up as Olaf the snowman, Menzel dressed up as Elsa, and Swift's backup singers donned reindeer outifts, before stripping away the costumes into slinkier duds. Swift posted a video of the costume swap on her Instagram feed.

Swift has made her epic 1989 world tour an open-door affair, inviting such A-list celebs as Julia Roberts, Ricky Martin, Pitbull, Lena Dunham and Mick Jagger to join her onstage.

Later this week, she'll take her talents to Singapore and Australia as 1989 goes international.