Opal is at a breaking point. Her best friends, Clara and Lyle, are being pulled away by other commitments, and her old teammates have ditched her because she got cut from the team. During a 16th birthday party, Opal runs into the forest, and her best friends follow. The last thing they expect is being chased by a monster and running through a portal that gets them stuck in a magical world. While Clara and Lyle plot strategies to escape, Opal explores the hub where the descendants of the gods live. Opal soon discovers she holds key information to a mystery in the magical world of the monsters disappearing. She and her two new friends, Finn and Anir, solve the mystery and present their information to the head of the magical society, Thoth. Thoth leaves to investigate the information further but fails to return to the hub after three days. With the disappearance of their leader, the hub is in turmoil. Clara and Lyle take advantage of this opportunity to escape, and Opal decides to join them. As the three girls are sneaking out, they are caught by Finn. He begrudgingly joins them and accidentally exposes Opal’s intentions of finding Thoth, not returning home. Despite the betrayal, Clara assists Opal’s quest. They find a warehouse, where humans have locked up hundreds of the monsters. Opal wants to save Thoth, to prove she’s worthy of joining the magical society, but Clara disagrees. Opal and Clara’s explosive argument gets them captured, but Lyle and Finn escape. During their capture, the two girls discuss their feelings and make-up. They also discover that the Greek Demi-Goddess of victory, Nike, is behind the kidnappings. She intends to use the monsters to wage war against the gods as revenge for being trapped on the mortal plane. Opal and Clara are finally rescued, and the group returns to the hub to get help but is too late. To save the gods, Opal and her friends must travel to the celestial plane, which is forbidden to do so, especially for mortals. They accept the challenge and get a weapon capable of stopping Nike. Against all odds, they sneak past beasts and defeat the demi-god. Despite the victory, the gods are angered by the kids’ presence. Opal stands up for them and the gods, moved by her speech, admit them into the magical society. Following a victory celebration, the trio return home.