Rachel, on a mission to tell Finn that he is not the father of Quinn's baby, tries to hint to the glee kids that Puck is actually the father with the hope that they'll tell Finn, but they already know and conspire to keep Rachel from telling Finn. Rachel tells Quinn that babies of Jewish parentage are at risk for a horrible genetic disorder, with the hope that Quinn will talk to Puck about it.
Will introduces Emma as the new Glee supervisor and receives an underwhelming response from the kids, who must now come up with their set list for Sectionals on their own.
Rachel offers to do the ballad, but Mercedes says she's sick of Rachel hogging the spotlight when Mercedes works just as hard as her. Mercedes proceeds to perform "And I'm Telling You", absolutely killing it, and Rachel concedes that Mercedes should perform the ballad.
After class, Finn tells Rachel that if they win Sectionals everything will be good for awhile. Rachel agrees - then proceeds to tell Finn that Puck is the father of Quinn's baby. Finn, livid, attacks Puck, breaks up with Quinn and quits glee.
Rachel apologizes to Quinn and says that she just wanted Finn to be hers. Quinn says she's not mad, but wants everyone to leave her alone, including Puck who confesses he wants to be with her and raise the baby.
The kids - minus Finn - arrive at Sectionals and are shocked when the other two teams perform all of their numbers. Will confronts Sue about leaking the set list and she laughs that this is the end of glee once and for all.
The kids scramble to put together a new routine, and are saved when Finn shows up with a song for the final number. Rachel begins with a show-stopping rendition of "Don't Rain on My Parade", followed by the entirety of New Directions performing "You Can't Always Get What You Want".
While the not-so-qualified judges deliberate, the Jane Addams squad coach confesses to cheating and apologizes to the kids. However, it's too late the judges have already made their decision.
When Will goes home to change for Emma and Ken's wedding, Teri confronts him and says that she knows that she made a mistake and she's getting help. Will says it's too little too late and leaves her.
Will arrives at the wedding reception to find Emma sitting alone in her dress. She tells him that her postponing the wedding for glee Sectionals was the last straw and he dumped her. Will apologizes, but Emma says that Ken's right, she was settling for him because she couldn't have Will. She also sent in her resignation to Figgins and will be leaving McKinley because it's too hard to be around him. Will tells her he just left his wife, but Emma feels like it's just too late.
Figgins meets with Sue and fires her from the Cheerios for sabotaging glee. She concedes this round to Will, but promises to come back in fighting form.
The glee kids show Will their winning trophy and perform "My Life Would Suck Without You" for him since he couldn't see them perform at Sectionals. Will confronts Emma and kisses her.