Sam and Rachel are growing closer on Glee Season 6 Episode 6 and open the episode with a duet of Dion Warwick's "I'll Never Fall In Love Again" and agree to meet up after school at Breadstix.
Brittany's parents tell her that her father is not her real father. On their honeymoon in England, Brittany's mom had sex with Stephen Hawking, so he is her real father. Despite her shock, she breaks the news that she and Santana are getting married and her parents react with glee.
After both Sam and Rachel confess to blowing off their date and to having feelings for one another, they accidentally say "I love you" before parting ways in the hall. Mercedes comes in to mentor the New Directions before Sectionals and asks Rachel what's going on between her and Sam. Rachel says she's not sure and Mercedes gives her the go-ahead to date Sam if that's what she wants.
Mercedes also tells Rachel that sooner or later, she's going to have to go back to Broadway. Mercedes knows about a new musical coming to New York and says she's gotten Rachel an audition. Rachel says she can't leave the students and Mercedes tells her the world isn't right without Rachel in front of an audience six nights a week and twice on Sundays. Rachel still isn't ready to go back.
Brittany asks Artie for help planning her wedding to Santana and their dream sequence features Blaine and Sam as angels on swings.
Mercedes hatches a plan to get Rachel back to New York and enlists the help of the glee club guys, plus Sam and Blaine.
Santana and Brittany discuss their guest list and Brittany thinks they should invite Santana's abuela. Santana says they can't because inviting her means she wouldn't be marrying Brittany and she would choose Brittany every time. Brittany hatches a plan to get Abuela on board.
Dressed as a candy striper, Brittany shows up at Abuela's house and they bond over telenovelas. When Abuela sees Brittany's engagement ring, she asks about Brittany's fiancee' and then Brittany invites her to appear on Fondue For Two. Santana watches and doesn't understand what Brittany's trying to do or why her abuela is so open about love with Brittany.
Mercedes has the guys sing "Arthur's Theme" to try and convince Rachel that New York City is where she should be. She remembers her fonder times there while they sing but ends the number doubting herself and telling them she's not ready to go back. Mercedes promises not to leave until she is.
Santana confronts Brittany about going behind her back to try and persuade Abuela to come to their wedding. Brittany ponders whether it might be their job to teach her that they're normal people just like she is.
Sam serenades Mercedes and then she reminds him they're just friends. She reveals that she's been dating and then encourages him to give it a go with Rachel.
Rachel asks Mercedes to watch over the glee club and slides an airline ticket across the piano in the choir room. She's decided to go to New York and audition for another musical. She has a bit of a breakdown first and reveals that she's scared of failing again. Mercedes reminds her everyone will fail many times over before achieving success and assures her no one laughs at her when she sings.
Brittany brings Abuela to the auditorium and Santana sings "Alfie" with the glee club, plus Blaine, backing her up. Brittany joins the backing choir mid-way through the performance and Abuela holds back tears as Santana sings. When the song is over, Brittany helps Abuela onto the stage and tells her that Santana is her fiancee. Abuela refuses to accept Santana and Brittany.
After returning to McKinley, Rachel tells Mercedes auditioning was exactly like returning home. Sam asks if she got the part and Mercedes punches him saying what really matters is that Rachel did it. She asks Sam out to dinner at Breadstix.
The glee club arrange "What The World Needs Now" for Brittany and Santana and then they all go to Will and Emma's apartment for Hanukkah. Blaine arrives without Dave.