In this semi-'Grease' themed episode, some graduated 'Glee' cast members return to help with the school musical, Finn (Cory Monteith) struggles to find his place in his new life and the students fight for the roles of their dreams.

With his failed plans of marrying Rachel (Lea Michele) and joining the army now all but lost to him, Finn finds himself working at the Hummel family tire shop. In the midst of his self-pity, he is visited by Artie (Kevin McHale) who wants Finn to co-direct the school musical 'Grease' to get him out of his funk.

Meanwhile, Blaine (Darren Criss) is debating participating in the musical because now that Kurt (Chris Colfer) and he are broken up he doesn't think he can take part in anything romantically themed. To express that he still loves Kurt, Blaine sings 'Hopelessly Devoted to You' from 'Grease.'

Blaine ends up auditioning for the play, but decides that he couldn't possibly be in it without breaking down. Finn leaves the room in anger because he thinks he's not qualified to be a co-director and Artie calls in his secret weapons: McKinley High alumni Mercedes (Amber Riley) and Mike (Harry Shum Jr).

Emma (Jayma Mays) and Will (Matthew Morrison) are still discussing how he plans to leave for Washington, with Coach Beiste (Dot Jones) as their relationship moderator. Will tells Emma he always wants them to be together because he loves her as an equal partner and she reluctantly agrees to travel with him.

Finn and Artie have trouble trying to find an appropriate Danny Zuko, so Finn heads out to the football field to locate a new recruit. There he finds Ryder Lynn (Blake Jenner) who is busy dancing in the end zone like a fool rather than actually playing football.

Inside the lady's room, Marley (Melissa Benoist) and Unique (Wade Adams) are discussing their preferred roles in the musical, with Marley holding out for Sandy and Unique wanting the female role of Rizzo. Sue (Jane Lynch), who just happens to overhear this, steps out and promises that she will not allow him to take on a gender-bending role in the play.

Marley and Unique audition with Pink's 'Blow Me (One Last Kiss)' and request the parts they would like to be chosen for, Sandy and Rizzo respectively.

Ryder is busy studying so he can stay on the football team when Finn arrives and invites him to audition in the auditorium later. He sees a lot of himself in the boy and they start bonding over their shared experiences. Together they sing 'Jukebox Hero' by Foreigner, which Finn counts as Ryder's audition.

Later in the day while Ryder is talking to Marley, Kitty (Becca Tobin) arrives to try and steal the spotlight away from her nemesis, informing Marley that she plans to audition for Sandy. She and Jake (Jacob Artist) sing Neon Trees' 'Everybody Talks' for their audition.

During callback discussion, Finn fights for Unique as Rizzo until Sue steps in and calls them to Principal Figgins' (Iqbal Theba) office to talk about their controversial casting. Sue seems concerned that this will open Unique up to bullying and Finn says he plans to cast Unique for the role regardless of what anyone else says.

Coach Beiste goes to have a frank discussion with Emma, telling her she should be honest with Will about not wanting to go to D.C. before the lies damage their relationship. She recommends that Emma tell Will her reservations before it's too late.

In order to pick a Danny and Sandy, Mercedes leads the potential candidates in a dance/sing off. Marley, Jake, Kitty and Ryder join her to perform another 'Grease' song: 'Born to Hand Jive.' Kitty spends the majority of the time being jealous of the attention given to Marley from both Jake and Ryder, which could ultimately cost her the role.

Later, in the library, Finn officially offers Unique the part of Rizzo and promises to help take care of anyone who stands in their way. Unique cries, finally happy to have found his true place. Finn smiles, mirroring Unique's sentiments.

The cast list goes up with Ryder cast as Danny and Marley cast as Sandy. Kitty, upon seeing her minor role, leaves in a huff, but not before insulting Marley as per usual.

When Will arrives at home, Emma is obsessively cooking. He finally gets her to stop and she admits that she doesn't want to go to Washington. The reason? She's worried she will resent him for taking her away from the job and the students she loves. They discuss what they both want in a partner, and agree to visit each other as often as possible. Will promises when he returns they will finally get married.

In the glee room the next day, Will tells Finn that he's leaving for a few months and the kids will need a leader, someone who can help make dreams come true. The episode ends with Will offering a shocked Finn the opportunity to run the glee club for the three months he's in Washington.

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