Chelsea, Austinʼs tutor, has a twin, Charlie, who is not that smart as her. Austin then mistakes Charlie as Chelsea, causing her to teach Austin the wrong information for his upcoming test. Meanwhile, Aaron visits the dentist for the first time since he was 4, after a traumatic experience. The group must then ensure he goes to the appointment and must dig into his past to get him to overcome his fear.
- Ross Lynch as Austin Moon
- Laura Marano as Ally Dawson
- Calum Worthy as Dezmond "Dez"
- Raini Rodriguez as Patricia Maria "Trish" De La Rosa
- Spencer Boldman as Aaron Moon
- Stefanie Scott as Lexi Reed
- Jack Griffo as Tyler Fox
- John Henson as Mike Moon
- Samantha Boscarino as Scarlett Malone
- Katie Cockrell as Chelsea
- Kellie Cockrell as Charlie
- Fred Henderson as Mr. Crocker