'Glee' spoilers: Jesse St. James, Adele & more scoop from the set of the 300th musical performance

glee-300-adele.jpgThat "Glee" has filmed 300 musical numbers is a pretty huge milestone already, but when you consider the fact that said numbers have been delivered over the span of just 50 episodes, it becomes an even more remarkable accomplishment.

Those tracks range from "Respect," Mercedes' New Directions audition in the pilot, to the 300th number, an Adele mash-up the cast filmed in front of an audience of press and crew members on Wednesday (Oct. 26).

Zap2it was there, and while we don't want to spoil too much about the performance, here are the details we will spill:

Mercedes and Santana share the leads on a lady-tastic mashup of Adele's "Rumor Has It" and "Someone Like You," which you will want to rush to your iTunes and purchase as soon as you hear it because it is so fantastic. Since this wasn't a New Directions song, they're joined by Sugar (of course) and another former N.D. member (you'll probably be able to guess who if you think logically for a second, and you'll be very happy about the vibe we observed between this person and another new group member). They are all wearing gorgeous flirty black dresses which we also covet. Basically everything about No. 300 is fabulous.

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After the performance, the entire cast -- including newbie Damian McGinty, who makes his debut in the Nov. 1 episode -- piled onstage to share a few thoughts about the milestone. Creator Ryan Murphy was also on hand to share some very important scoop. Here's what we learned:

First things first: Jonathan Groff is back! Murphy says that Jesse St. James is returning this year as the coach of Vocal Adrenaline, and he'll share "many scenes" with "Glee Project" runner-up Alex Newell.

Speaking of Newell, he'll be taken under the wing of "Kurt and Mercedes, and will turn to them for much advice. So he'll have stories with those two lovely actors," Murphy says. 

Newell's co-runner-up,  Lindsay Pearce, will be back in episode eight. "She is sort of the Rachel of her school, and she's so amazing, and she will be competing against our groups," Murphy says. 

As for McGinty's co-winner Samuel Larson, his entrance isn't fully concrete yet -- they're working on the script for episode eight right now -- but expect to see him in the new year. "Sam is probably going to come in we think around episode 10 or 11, probably after the Christmas break," Murphy says, "in January with a new start, a new semester."

The Adele mash-up came about thanks to the singer herself, with a little help from star Amber Riley. "Someone actually e-mailed me a video of Adele saying that she wanted me to sing her song, so I e-mailed it to Brad [Falchuk] and Ryan. So I think that's how we got 'Rumor Has It' and 'Someone Like You,'" Riley shares.

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"Yeah, Amber's been on that kick for literally about eight months," Murphy says. "Which is a wonderful thing, because I love to hear the cast have passion for music. Who do they love; why do they love it? So many of the songs that we've done on this show -- if we've done 300, I'd say 50 of them have come from me hanging out with the cast and them saying 'Oh I really want to do this, and this is how my character would do it' and then lo and behold, three months later I'll ... put it into the script."

For the record, the 300th song is approved by the original artist herself. "Adele heard the track on Monday and she loved it," Columbia Records chairman Rob Stringer tells the cast. "She's a big fan of the show."

Before they left to continue filming, the cast shared their favorite musical numbers from the show. Diplomatically, none of them chose their own solos -- and some of their answers will surprise you. Tough guy Mark Salling says "Defying Gravity" really "struck a chord," and Corey Monteith admits he "got a little misty" the first time he heard "Bust Your Windows" because "it was so awesome." The adorable McGinty joked that "it's been a tough three years" -- by the way, the cast laughed adorably at everything he said -- before choosing "Jesse's Girl" as his personal favorite. Did we mention he is adorable? Because he and his pompadour are super adorable.

By the way, according to the press release we received with a six-page list of all 300 songs "Glee" has filmed, the tunes we haven't yet heard -- in order -- are "Being Green," "Last Friday Night," "Candy Man," "Waiting for a Girl Like You," "Take Care of Yourself," "Tonight," "Uptown Girl," "A Boy Like That," "America," "One Hand, One Heart," "Hot for Teacher," "You and I/You and I," Hit Me With Your Best Shot/One Way or Another," "Oklahoma" and a Hall and Oates mash-up. It skews a little "West Side Story"-heavy, considering the McKinley High drama club will be working on the musical through episode five.

One last tidbit of scoop to tide you over until the first new "Glee" episode in a month: there will be one tribute episode this year, in the spring, and it's the big one they've been working on pulling together for two years now.

The 300th musical number airs Nov. 15 in episode six, which is called "Mash Off."

Check out more pics from the performance below: 

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Photo/Video credit: Fox