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A Bunch Of Famous 'Cool Kids' Joined Taylor Swift's 1989 Tour

Tay surprised her Philadelphia fans with amazing appearances by some of her BFFs.

Poor Taylor Swift. As she gallivants from city to city on her 1989 World Tour, she barely has any chances to see her friends and indulge in some much-needed girl time. Right?

HA — WRONG!

Just a couple weeks after shocking her Detroit fans with concert cameos by Imagine Dragons, Martha Hunt and Gigi Hadid, Tay upped the ante yet again during her show in Philadelphia last night (June 12).

First, she was joined onstage by Echosmith for a rendition of the group’s hit “Cool Kids.”

“So what can I do to surprise Philadelphia?” Taylor teased the crowd. “OK, so there’s this song that came out this past year, and it embodied what we all feel when we feel like there’s these people who feel so cool that you can’t catch up with them. You can’t get on their level, and you know they’re just like cool kids.”

The crowd erupted as the band launched into the catchy tune, with Taylor and frontwoman Sydney Sierota making a predictably awesome team.

Taylor and Sydney also indulged in some girl time backstage, posing for cute selfies together.

That surprise appearance alone was probably enough to send Swifties into full-fledged freakout mode, but Taylor wasn’t done making it the best night ever.

She also reunited with her fierce-as-hell “Bad Blood” costars Mother Chucker and Justice (a.k.a. Cara Delevingne and Mariska Hargitay). The supermodel and the “Law & Order: SVU” actress (whose character, Olivia Benson, is also the namesake of one of Tay’s kitties) strutted down the runway with Taylor during “Style,” werking their sass with roaring approval from the crowd.

“Couldn't even contain my happiness because @caradelevingne and @therealmariskahargitay surprised the crowd tonight. #1989TourPhilly,” Taylor wrote on Instagram. Cara later reposted the same pic, calling it “a special night.”

Taylor also shared a clip of the trio giving us major #SquadGoals, saying “WHAT EVEN HAPPENED IN PHILLY.”

After the show, Cara shared a selfie with Taylor accompanied by the super sweet caption, “I am so proud to call you my friend @taylorswift what an amazing show! You blew my brains as per usual! Keep inspiring the generations to come x #tillweare100”

So, let’s tally it up: we’ve now seen a total of four “Bad Blood” vixens join Taylor on tour, which means we only have about 7,573,920 to go. Any guesses on who will be next?!