Brendon Urie and co were playing at the Corona Capital Festival in Mexico City and invited Halsey to join them after her set earlier in the day.
Posting on Instagram after the performance, Halsey wrote: “Wow @coronacapital love u @brendonurie ur my hero for ever.”
panic brought out halsey tonight to sing I write sins, the emo JUMPED out !!!! imagine going from being a stan of someone to then bringing you out at shows years later !!!! pic.twitter.com/xYpxmVzoPb
— sabrina??♀️? (@_sabrinalana_) November 18, 2018
The pair are known for their close friendship, and Halsey previously revealed how she opened up to Urie about being bullied at school.
Speaking about her time growing up in Edison, New Jersey, Halsey told NME how she was bullied at school because of her obsession with emo bands of the noughties.
Following Panic! At the Disco up and down the East Coast as a teenager, Halsey recalls interacting with Urie at one of his shows.
“I remember having this wristband from the pit [at one of the shows], and Brendon Urie being on the edge of the stage and acknowledging me…so I wore that wristband every day. I even covered it with plastic when I showered so it wouldn’t fall off.”
Halsey described how an altercation with one of her bullies at school led to the wristband breaking. “I was devastated… I couldn’t understand how somebody could be so mean.”
As her popularity and fame grew, Halsey recalls meeting Urie again and recounting the incident with the bullies to him; she now considers the frontman a friend.
“I went back to my dressing room after [a show of mine he came to recently]…and there was a bouquet of flowers and two plastic Panic! At the Disco wristbands, with a little note that said: “This is to replace the one you lost.”
Meanwhile, Panic! At The Disco! will return to the UK for a massive tour in March next year.