Sofia thinks the time has come to take her friends and family to the Mystic Isles. However, she learns that Daisy, a member of the rescue squad at the Park of Rainbow Tigers, knows about the Amulet of Avalor because she's from that kingdom and joined to overthrow Shuriki. Sofia invites Daisy and Sara to join her on her next trip to the Mystic Isles. But when they get there, the group is in for an unpleasant surprise.

Princesses Amber, Clio, and Hildegard have no idea what to write in their diaries. Then they notice that Sofia has been acting differently, and they sense that she's in love. When Sofia isn't looking, the three princesses read in her diary that she has a crush on Prince Hugo and she'll be dancing at the upcoming springtime ball with him. Jealous of her sister's crush, Amber decides to come between them. She tries to make Hugo jealous by flirting with Prince Desmond, and she tries to make Sofia jealous by flirting with Hugo. But this only intimidates Desmond and rattles Hugo's nerves

Sofia and Prince Hugo are going to Avalor with their families, and they've invited Sara, Daisy, and their families to join them, too. Amber also wants to visit the Isle of Jaquins in the Mystic Isles only for Daisy to reveal that Jaquins have their own special realm: Vallestrella. Amber really wants to visit Vallestrella, but Daisy says that humans are not allowed in Vallestrella. Once in Avalor, Amber asks two Jaquins to take her to Vallestrella, and Sofia comes along when she finds out. But what happens when Amber accidentally releases a moth fairy who gets loose into Avalor?

Sofia has been a protector for a year, she thought her biggest challenge was over when she defeated Vor but that isn't the case, now she will have to face an even bigger challenge, her family. The Tri-Kingdom area is at war and it feels as she will never be able to stop it. At least until a princess comes to help.

History repeats itself when Hildegard and Clio find out about Sofia's and Prince Hugo's identities as Protectors of the Ever Realm. Hildegard wants to wear an Enchantlet, and Sofia and Hugo won't let her wear either of theirs. During a sleepover at Enchancia Castle, Hildegard steals Sofia's Enchantlet and tricks a trio of Wee Sprites into believing she herself is a Protector, thus causing trouble for the Sugar Plum Fairy. Can the royals and Protectors fix this mess?

If Amber can cause trouble just by coveting what Sofia has, wait until Hildegard does the same. Hildegard becomes jealous when she learns about Sofia's magical amulet. While Hildegard sleeps over at Enchancia Castle, she steals the Amulet while Sofia is sleeping. But stealing the Amulet is a very bad deed, so the Amulet curses Hildegard by bringing Sofia's old foe, Prisma, to the Ever Realm! Now that Prisma is here, she's determined to cover the Ever Realm with magic crystals! Sofia is angry at Hildegard for betraying her trust. Can Sofia forgive Hildegard for her carelessness? More importantly, will Hildegard find a way to break this curse?

James has some of his friends over for a sleep over on the same night Sofia and Amber are hosting their own slumber party. However, both parties accidentally get locked in the observatory and can't get out.

During the 41 years of being trapped inside the Amulet of Avalor, Princess Elena had chosen princesses to wear it to see who had what it took to release her...and the only princess to do that was Sofia. But Amber wonders why Elena never picked her to wear the Amulet.

Sofia has been a protector for a year and now she finally gets to be at the meetings only for official protectors. This meeting is a special one, every year a protector gets to nominate a candidate from their own Isle or in Sofia's case Realm. Hugo, Lucinda, and Clio show that they have what it takes to be a protector but she can only choose one. Will it be Hugo, a Prince who has a duty to protect his kingdom, Lucinda the witch who bettered herself and started caring about others instead, or Clio who has started listening to her own voice?

It's been a while since Sofia freed Princess Elena from the Amulet of Avalor. Now Sofia has a beautiful new dress, and her amulet is pink. Everyone at Royal Prep loves Sofia's new gown and amulet. However, Princess Hildegard is jealous because everyone thinks Sofia's ruby pink amulet is prettier than her new ruby necklace. Hildy wants the ruby pink color to look pretty with her gown, so when Sofia isn't looking, Hildegard steals the amulet. But before she even has a chance to put it on, the amulet disappears along with Hildegard's necklace! Where could the amulet have gone? Could the answer be under everyone's noses?