Sue gets musical when she joins the glee club. Sam starts a tribute band. Meanwhile, Rachel wants to elevate her social status and gets help from an interesting source when Brittany comes to her rescue.
It's Christmas time at McKinley High and Finn tries to get everyone in the holiday spirit; Brittany needs no help because she still believes in Santa Claus. In other news, Sue scams the teacher's Secret Santa.
New Directions heads to sectionals against fierce competition including the Hipsters and Dalton Academy's Warblers who shine with their newest member: Kurt. Meanwhile, romantic troubles begin for couples Emma and Carl as well as Finn and Rachel.
Sue's mother (Carol Burnett) comes to town after years away which causes some revelations in the Sylvester family. Meanwhile, Burt and Carole announce that they are getting married, and the Kurt-Karofsky situation gets out of control.
In order to prepare for Sectionals this year, Mr. Shue hosts the second annual "Boys vs. Girls" mash-ups competition. Meanwhile, Puck gets out of juvie and strikes up a new friendship while Kurt makes a new friend from another school.