Years after the gang has gone their separate ways, Ally, Austin, Trish and Dez meet-up and learn what they have all been up to, individually.
As the rest of the group prepares for the next phase of their lives, Trish is still determining what her next steps will be.
One of Austin & Ally’s music students is upset about spending Christmas away from her father, so the gang does everything they can to try and make her happy and realize that they’re her family too.
When a missing library book threatens to keep Ally from graduating, Austin tries to find it. Meanwhile, Trish fakes some memorable moments in an attempt to get more photos in the yearbook.
When Ally is rejected from college, she decides to let go of her "perfect student" ways. Meanwhile, Austin and Dez discover their favorite childhood ride will shut down forever.
While visiting New York the group attends the Central Park Spooktacular, and it inspires them to tell their own scary stories.
Ally learns that the new woman her Dad is seeing also happens to be the mom of a very difficult student at the A&A Music Factory.
When Trish’s boy-band client “Boynado” threatens to split up, she searches to find a way to fix their problems. Meanwhile, Austin and Ally try to help a former impersonator find his own voice.
A visit with a fortune teller convinces Austin that something bad will happen during his comeback concert. Meanwhile, Trish believes she is going to meet a prince.
A mystery unfurls when Ally’s songbook is stolen from her school’s ’70s-themed party and the gang sets out in search of the culprit.
Ally is performing at an awards show but the producers are worried about her dancing abilities.
The gang prepares for the A&A Music Factory's first showcase and Austin wants to surprise Ally by teaching their students one of her songs.
Desperate to perform again, Austin begins singing at a karaoke club in disguise. Back at the A&A Music Factory, Ally mentors a student with stage fright.
When Austin and Ally are paired together in Home Ec, they get to imagine life together as a married couple. Meanwhile, Trish helps Dez book a job directing a commercial.
Trish books Billie and Bobbie of "The Billie and Bobbie Show," a famous brother and sister duo, to talk and perform with the students of the A&A Music Factory. Meanwhile, when a code inspector comes to look at the music school and threatens to shut it down, the foursome learns the famous duo have ulterior motives.
Ally wants to prove to Austin that she can unlock the hidden musical talent of a new student.
The foursome's plans to enjoy their senior year together are put on hold when Austin learns that he's a credit short.
The gang has less than a week to teach first-time music students how to play in a band in anticipation of the A&A Music Factory's grand opening.
Unable to find a new passion, Austin feels forced to take a job at his parents' mattress store, and Ally struggles to keep up with an influx of music students. Dez and Trish try and help the duo to come up with a plan that will solve both of their problems.
The gang shares an emotional reunion in Miami at Ally's triumphant homecoming gig. When Austin learns that the foursome's time together is only temporary, he contemplates enrolling in military school.
