Taylor Swift heads to Glee to film bizarre episode of Season 5

If you're both a Swiftie and a Gleek, you know that Taylor Swift's connection to " Glee " goes far beyond the music she performs on the show, which has only happened twice, "Mean" and "Mine" in seasons three and four respectively. Early in the show's six-season run, Swift was photographed hanging out with Cord Overstreet and Corey Monteith — who, according to fan theories, might even be a Minecraft star 》The source of inspiration.

There's also Swift's friendship with Diana Agron, which some fans believe is more than just platonic. While Agron debunked the rumors long ago, it's clear that the Glee cast became friends with Swift through Agron anyway. In fact, Swift was even on set while filming the fifth season episode "The Test." Kevin McHale and Jenna Ushkowitz discussed the unexpected visit on the Jan. 26 episode of the "This Is What You Really Missed" podcast.

On 2014's Glee , Artie tested positive for chlamydia and at one point pretended to be an actual STD patient (no, really), which was McHale's least favorite character storyline. But the shooting wasn't that bad, he said. "It's fun because it's crazy."

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McHale learned that Swift was on set while filming one of the episode's musical numbers. "She was filming at Paramount that day, and we all met her through Diana." The visit made McHale feel "very famous," he continued. "I was like, 'Don't worry, guys, we're friends. It's okay.'"

Agron herself may not have been present during Swift's visit, as her only two episodes of "Glee" season 5, "The 100" and "New Directions," aired weeks before "The Test" . But apparently, Swift had other familiar faces welcoming her to the set.

Although "tested" "Glee" itself is an odd entry that tends to rank pretty low in popularity among other "Glee" episodes, and maybe knowing that Swift is hanging out in the background will make your rewatching experience a little more fun. While this seemed like the perfect opportunity for Swift to guest star on Glee , it simply wasn't possible — despite creator Ryan Murphy revealing during an earlier podcast appearance that he regretted it. "I really wanted to do a tribute to Taylor Swift... I think she's amazing and those songs would be perfect on 'Glee ,'" he said. "Taylor Swift is the one who gets away with it."