That is to say, the episode opens with a pair of red lips on a black screen, the iconic Rocky Horror Picture Show image. And those lips are singing "Science Fiction Double Feature." It's a nice performance of the song, and a great way to start the episode. I know there was some debate about who was singing this song, but the Eagle-Eyed Forum Posters have informed me that the guy in charge of the show's music has confirmed that it is Santana (also known by her human name of Naya Rivera). If I had any doubts about whose lips these were, they were erased by the tiny smirk they give at the very end of the song. Nobody can convey as much smirkiness with such a tiny movement of her lips as Ms. Santana Lopez.
And as soon as that song is finished, we're right into another. We hear the opening notes of "Over at the Frankenstein Place," and we're in the auditorium, where there's a full set showing Frank-n-Furter's castle from the outside. (And kids, don't forget -- if you ever get a flat tire on a rainy night and your boyfriend suggests walking to the nearby castle to call for a tow, just remind him that castles don't have phones. And then dump him, because he's an asshole.) Rachel, in costume and holding a newspaper over her head, is singing the song. In addition to the set, there's a massive amount of fog rolling off the edge of the stage. Finn's on stage, also in costume (complete with dorky Brad glasses), and he joins in the song. And the other kids, as Rocky Horror partygoers, are singing backup from their hiding places in the shrubbery. The song is cut off as Hot Dentist Carl (played by Hot John Stamos) walks onto the stage, in full leather, and accuses Will (who's sitting in the empty auditorium, directing) of "messing with [his] woman." We get a freeze-frame of Will's panicky face -- he looks like he's trying to chew through a particularly tough piece of gristle. In voice-over, he wonders how "did a production of Rocky Horror turn into... my horror?" I think this question calls for a flashback.
The producers agree with me, as we flash back to the teachers' lounge one week ago (as Will's V.O. tells us). Emma's nibbling on a sandwich like a super cute chipmunk when Will sits down at her table. Will looks at her sandwich and asks her why she allowed the crust, which she normally consigns to oblivion, to stay on the bread. With a puzzled look, she glances down at the sandwich and tells him that she must have forgotten. Wait, does this mean she's from the same place as Fauxlivia? Because I am not coming up with nicknames for an alternate-universe set of Gleeks. Oh, actually, it's just that she had such an amazing weekend with Hot Dentist Carl that she finally unclenched her sphincter for five minutes and didn't freak out over her lunch. Said weekend included a midnight show of Rocky Horror at the local corn-syrup encrusted "revival" movie theater. Emma was apparently unclenched all weekend, because she went to the gross theater and was surrounded by a bunch of gross nerds in costumes and didn't even care about the toast, water, and rice flying through the air. We get a very quick flashback to her at the theater with Hot Dentist Carl, throwing toast of her own. (That's not a euphemism.)