Rachel is putting bottle after bottle of pills down on the piano. Will asks her what's up, and she explains that she's taking vitamin supplements three times a day because she's exhausted. And she tells him that's because every song she sings in Glee Club is a solo. She continues, as we flash back to a rehearsal: "As you know, I have perfect pitch. Which also means I have a very sensitive ear. None of them were singing." The choir is warming up, and we see a bunch of them doing a completely lackluster job with their "mi-mi-mis" and their "ma-ma-mas." So Rachel had a talk with Lauren, the president of the A.V. club, who also happens to be the female wrestler from the Old Maids Club. She and Rachel are having a clandestine meeting in the stairwell. Lauren is almost offended at the simplicity of Rachel's request, which is that she bug the choir room to get proof that the other kids aren't singing. As some random student walks up the stairs, Lauren shoots him a sidelong glance and asks Rachel, "Who's this guy? Who is this guy?" And then she won't say a word until the potential eavesdropper is gone. Hee. After demanding payment in the form of candy, Lauren agrees to do it. Someone should explain to her that cash can be used to purchase items like candy. The bug is installed, the recording is made (on these big reels of tape -- in addition to learning about currency, Lauren should bone up on digital technology), and Rachel listens to the tape to figure out exactly which voices are missing. The best thing about this is that we get lots of close-ups of Rachel doing her warm-ups, which she performs with a deranged eyes-wide pageant glare. The end result of this is a list of five club members that aren't singing, which Rachel hands over to Will.