Cat Windsor (Ariana Grande), Jenny Blanchard (Daniella Monet), and Miranda Simms (Elisabeth Gilles) are all mean girls and Cat is the head leader of the mean girls group (The Plastics) and Ross Lynch, Riker Lynch, Rocky Lynch, Ryland Lynch are all friends with Cat but except Rydel Lynch and Ellington Ratliff who hate her guts..... But Ross is dating Cat and here a new girl named Cathryn (Victoria Justice) moves up with the girls and becomes friends with Rydel and Ratliff and falls in love with Ross as well.... But she knows that he is hers so she dates Riker instead.....