Figgins alerts Will to an epidemic at McKinley: alcohol abuse. Students are blatantly coming to school drunk from new alcoholic beverages targeted to kids with pop songs glamorizing binge drinking ("just listen to Ke-Dollar-Sign-Ha"). To promote Alcohol Awareness Week, Figgins charges Will and the glee club with performing an anti-alcohol song at the assembly.
Will approaches Emma, hoping to be friends again. When Will reveals that he's not dating anyone, Emma says that he should be. But Sue appears to suggest that Will first enroll in Alcoholic Anonymous - as a future alcoholic, given the loser status of his life. When her glee club (which she's coaching after a stairwell fall by Oral Intensity's prior teacher - a fall that Sue caused) crushes his, he'll surely turn to drink.
Puck flirts with Rachel after learning that her dads will be out of town for the weekend; he's trying to persuade her to have a party for the glee club. She resists, and Puck tells Rachel that her dads trust her because "you suck and you're boring."
Rachel breaks the tension with Finn by giving him a hug and tries out the original song he prompted her to attempt: "My Headband" ("Write about what you know," she says). Finn's unimpressed but supportive, and suggests that if she wants to write a song like those by Carole King or Joni Mitchell she may need to live a little more. She agrees: her "journey from 'Little Princess' to 'Natural Woman' begins Saturday night at my house."
The glee club students decide to attend Rachel's "house party train-wreck extravaganza" as long as there's alcohol involved. Rachel welcomes the show choir - along with Warblers Kurt and Blaine - into her dads' "Oscar Room" (complete with a mini-stage for Rachel's impromptu performances) and hands out drink tickets for wine coolers. Quinn is saddened to find Sam and Santana making out at the party, and the rest of the students are about to ditch the party until Puck gets Rachel's permission to break into her dads' liquor cabinet.
The kids party and get drunk to Far East Movement's "Like a G6," and a non-drinking Finn and Kurt deal with sloppy drunks Rachel and Blaine. Finn walks Rachel through the various drunken archetypes New Directions are acting out: Santana is the weepy, hysterical drunk, melting down on Sam over Quinn; Quinn and Lauren are the angry girl drunks, tearing into Puck; Brittany is the drunk girl who turns into a stripper; Mercedes and Tina are the happy drunks; and Rachel is the needy-girl drunk, clinging to him.
To prove him wrong, Rachel insists on playing Spin the Bottle. During her turn, the bottle lands on Blaine: they kiss, and to everyone's surprise (especially Kurt's) both Rachel and Blaine feel a spark between them ("Your face tastes awesome," she tells him). Rachel and Blaine perform to Human League's "Don't You Want Me," and Rachel grows even more smitten with her duet partner.
The next morning, Kurt's dad, Burt, is taken aback to find Kurt getting ready in his bedroom as a hungover Blaine groggily awakes in Kurt's bed. At McKinley, the glee club members are all hurting from the night's festivities, and Artie passes out a thermos of Bloody Marys as "hair of the dog."
They all launch into a rendition of Jamie Foxx's "Blame It on the Alcohol," which becomes the production number they rehearse for Will in class. Will likes the number but is concerned that the song isn't anti-alcohol enough, and the kids challenge him on the issue, calling him a hypocrite because he drinks himself.
Will commiserates with Coach Beiste, feeling out of touch as well as beset by various angst-y personal issues. Beiste tells him that he needs to get a little "ridiculous" and burn off his stress, and she insists that he join her at her favorite honky tonk bar, Rosalita's Roadhouse.
Rachel calls Blaine and asks him out on a date. At first Kurt is amused until he realizes that Blaine accepted. Blaine argues that while he thought he was gay, it may be time to experiment and discover more about himself - maybe he's bisexual. Kurt gets angry, thinking Blaine is both fooling himself and leading Rachel on. He has admired that Blaine was out and proud, but Blaine admits that he's not as confident about who he is as Kurt assumes and, hurt that Kurt's judging him, storms out of the coffee shop.
At Rosalita's Roadhouse, Will and Beiste dance onstage and duet on Amos Milburn's blues classic "One Bourbon, One Scotch and One Beer," stirring up the crowd and downing their share of shots. Meanwhile, Kurt helps with party cleanup at Rachel's, and she knows he just wants to hear about her date with Blaine. She describes their lovely evening watching "Love Story" at the revival theater while dressed as the characters ("That's not gay at all," humphs Kurt).
Rachel thinks that if Blaine is not actually gay, she's kind of doing Kurt a favor, while Kurt argues back that Blaine is "the first of a long line of conflicted men you will date," and that as a couple they'll never have real chemistry. Rachel decides that she'll settle the issue by kissing Blaine while they're both sober.
A very inebriated Will and Coach Beiste make it safely - and responsibly, having cabbed it - back to Will's apartment. They agree that drinking can be fun, but Beiste reminds him they're not teenagers. They can't lecture the kids; they can only educate them and hope they make smart choices. After the Coach leaves, Will charitably grades papers while drunk, doling out A-pluses, and then, after fumbling with his phone, attempts to drunk-dial someone.
The next day at school, the hungover Will apologizes to Emma for the call, but she never received it. Sue takes the opportunity to torment Will once again by insisting that he has an alcohol problem.
Kurt vents about Blaine to his dad, but Burt is more concerned about Blaine sleeping over, insisting that Kurt get his permission beforehand. Kurt explains that it was innocent, but Burt's concerned about Kurt acting inappropriately under his roof. They argue about the details, but Burt insists on an apology. Kurt gives in, but asks Burt to educate himself more about gay relationships so that he can come to him with questions like any straight son could.
The glee club students are extremely anxious before their assembly performance, but - in accordance with "old Broadway tradition" - Rachel provides shots of a potent mixture from the remnants of her dads' liquor cabinet to calm their nerves. Principal Figgins introduces New Directions' number ("Tick and also Tock, by Ke-Dollar Sign-Ha") and they perform "Tick Tock"; all goes smoothly until lead singer Brittany suddenly throws up on Rachel, prompting a chain reaction vomit from Santana as well.
The next day, Sue makes an announcement over the P.A., blaming the assembly spectacle on Will. Sue reveals that she was the recipient of Will's drunk-dial, and she plays the message for the entire school to hear: Will drunkenly makes a play for one night of "getting crazy" with Emma (surprisingly, hearing it in her office, Emma's not upset).
Will and the glee club bicker over drinking as they wait in Figgins' office, but Figgins' reaction surprises them: he thinks the assembly disaster was staged with special effects, and the result has scared the rest of the students off alcohol. He congratulates them all (though quietly suggests that Will deal with his issues).
Will tells his students that, while he's relieved they got off the hook, he never wants them to pull something like that again. He vows not to drink anymore and asks the students to join him - at least, to be realistic, until after nationals. He asks the students to sign a pledge against drinking, and the agreement includes his phone number. If they slip, they can call him any time day or night to get a ride home. The students agree.
Rachel and Kurt await Blaine's arrival at the coffee shop, with Rachel excited to learn if she will end up "with a new boyfriend who can keep up with me vocally and give me vaguely Eurasian-looking children." As soon as he enters, Rachel kisses Blaine passionately. His response: "Yep, I'm gay. One hundred percent gay." He thanks her for clearing that up for him. Kurt's about to console her, but Rachel is surprisingly happy, too: "I just had a relationship with a man who turned out to be gay," she explains. "That is songwriting GOLD!"