McKinley High School's Glee Club used to be at the top of the show choir world, but years later, it has turned into a haven for misfits and social outcasts. But at McKinley, things for the Glee Club are about to change. Optimistic high school teacher Will Schuester has offered to take on the Herculean task of restoring McKinley's Glee Club to its former glory. Will's only hope lies with two true talents: Rachel Berry, a perfectionist firecracker who is convinced that show choir is her ticket to stardom; and Finn Hudson, the popular high school quarterback who must protect his reputation. Even though everyone around him thinks he's nuts, Will is determined to prove them all wrong and lead the glee club to the greatest competition of them all: Nationals.

After a tough loss at Regionals, the glee club is back as the underdogs of McKinley High. When the school is faced with even more budget cuts, Mr. Schuester pushes the kids to help recruit new members for the club. Rachel and Finn disagree on new recruits, including Sam Evans and exchange student Sunshine Corazon. New Directions now have their sights set on making it to Nationals and defeating their arch rivals, Vocal Adrenaline. With his heart in the right place, Will is determined to help the kids take Nationals, but at every turn he must battle with his nemesis, Sue Sylvester, the conniving cheerleading coach.

Season Three follows the Club through the sectional, regional and national show choir competitions, and during nationals they finally take home the winning prize. Season Three also introduced several new characters, such as Sugar Motta, Sebastian Smythe, and the winners of The Glee Project: Rory Flanagan, Joe Hart, Wade "Unique" Adams, and Harmony.

The season introduced several new characters, such as Jake Puckerman, Marley Rose, Kitty Wilde, Hunter Clarington, and winner and runner up of The Glee Project, Ryder Lynn and Betty Pillsbury respectively, it also counts with the return of Unique Adams. New characters were introduced as the plot focuses on the new generation of the New Directions due to the loss of several members after graduation. The plot also focuses on Rachel's college experience in New York as well as what the rest of the alumni are doing after graduation.

Finding the right note pales in comparison to navigating real life for the members and alums of William McKinley High School's glee club.

The show's final season sees a humbled Rachel return home, Kurt and Blaine at a crossroads and the glee club's future imperiled.