Glee's Ryan Murphy on Finn Tribute: "It Was Incredibly Difficult to Work On"

Glee's upcoming tribute to Finn Hudson, and the late Cory Monteith, is sure to be an emotional hour for viewers at home, and it was even tougher to make.

"It was incredibly difficult to work on," co-creator and executive producer Ryan Murphy told reporters Thursday at a screening for his FX drama American Horror Story: Coven. "It was very difficult to shoot."

The episode, which airs Oct. 10 at 9/8c on Fox, will follow Finn's family and friends as they grapple with his death and celebrate his life. The episode is said to feature covers of Adele's "Make You Feel My Love" and The Pretenders' "I'll Stand By You" — one of Finn's first, and most memorable solos on the series.

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"Almost everything in that episode is from the first take of every performance because ... the actors and the crew had a really hard time shooting it. I've never seen a crew that you can't continue shooting because they've left the room sobbing," Murphy said. "I struggled even working on it because what you're seeing is what they felt about not just Finn, but Cory. So I think it's amazing performances across the board, and everybody went into it with a lot of love."

That everybody includes several returning actors, such as Mark Salling, Mike O'Malley and Rosy Rosemont, all of whom have not been seen on the show in some time. Murphy said several actors, such as Iqbal Theba, reached out to him about appearing in the episode. "When you write something like that, there's no right way to do it," Murphy said. "So we wrote it. We put people who were under contract to the show in it, and a lot of the actors contacted me and said, 'I just loved him so much. Can I just please be a part of it?'"

Although Murphy discussed the difficulty in writing the episode, portions of the episode aren't scripted but are "what really happened" as a natural consequence of Monteith's close bonds with the cast and crew. "Those actors and the creators really, really loved Cory," he said. "People still are not over it. It's still very, very difficult."

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Murphy pointed to the episode's title, "The Quarterback," in explaining Monteith's role on set. "Cory really was that to that group of people and to me particularly, and there was nobody on that crew that did not like Cory," he said. "That group of kids, particularly, went through the limelight and became world famous at a very difficult age and many of them really struggled with it/ And Cory obviously very much struggled with it, but never on the surface, and I think that's why everybody loved him."

Despite the emotional strain behind the scenes, Murphy felt confident about the final outcome. "I'm very proud of it," he said of the episode. "I think the performances are quite stunning."

Watch the promo for "The Quarterback" now:

Glee airs Thursdays at 9/8c on Fox.

Reporting by Natalie Abrams