Last night wasn’t just Halloween — it was also the last stop in the American leg of Taylor Swift’s 1989 world tour. (Aren’t you going to miss playing the game of Which Celebrity Will Join The Squad Next?) At her show in Tampa, Taylor Swift welcomed Frozen star Idina Menzel to the stage, and the two sang “Let It Go” as a duet, with Menzel dressed as Elsa and Swift dressed as Olaf. She also brought Alessia Cara out to perform her hit single “Here.” Watch both performances below, and check out what your other favorite pop stars and musicians wore for Halloween here.

"The cold never bothered me anyway." QUICK CHANGE @idinamenzel

A video posted by Taylor Swift (@taylorswift) on Oct 31, 2015 at 10:23pm PDT

Thank you @taylorswift! That was definitely an out of body experience. Or out of Elsa's body experience! #1989tourtampa

A video posted by Idina Menzel (@idinamenzel) on Oct 31, 2015 at 7:46pm PDT

Frozen totally happened tonight. And 55,000 people sang 'Let it Go' so loudly, it nearly took my breath away. Good times, @idinamenzel ?

A photo posted by Taylor Swift (@taylorswift) on Nov 1, 2015 at 1:14am PST

Olaf vibes.

A photo posted by Taylor Swift (@taylorswift) on Oct 31, 2015 at 10:25pm PDT

Happy Halloween!

A video posted by Taylor Swift (@taylorswift) on Oct 31, 2015 at 10:24pm PDT

@taylorswift thank you for showing me what 55,000 people looks like. you are the classiest, sweetest, most lovely person and I can't thank you enough for what just happened. Also I can't feel my body. goodnight everyone I quit life.

A video posted by ALESSIA CARA (@alessiasmusic) on Oct 31, 2015 at 10:48pm PDT

Getting to share the stage with @alessiasmusic during 'Here'. Honestly couldn't be more impressed by this girl.

A video posted by Taylor Swift (@taylorswift) on Oct 31, 2015 at 10:20pm PDT

wait what happened last night

A photo posted by ALESSIA CARA (@alessiasmusic) on Nov 1, 2015 at 5:23am PST