Princess Sofia has had a lot of exciting adventures, from becoming a princess overnight to freeing Princess Elena from the Amulet of Avalor. Even being trapped inside her amulet was an adventure for her. As storykeeper of the Secret Library, Sofia has been having even more exciting adventures. She had to give each story a happy ending, and she had already done it four times. It wasn't easy—especially with all the plot twists—but it was worth it. But there were more exciting adventures for Sofia coming her way.

It was a beautiful sunny day, but Sofia had nothing to do. Her big brother and sister, Amber and James, were out with their friends, and Queen Miranda and King Roland II had royal duties to take care of.

Suddenly, Sofia's ruby pink amulet started to glow blue. That meant the Secret Library was summoning her. Luckily, Sofia was already wearing her blue flying derby clothes, which she usually wore for Secret Library missions. Sofia grabbed her book Behind the Walls and went through the entrance to the secret passageway. After going down the stairs, she got into a boat shaped like a tiara and rode down the hidden river. She reached the Secret Library entrance and put the book in the lock, and the doors opened.

"Okay, I'm here," Sofia told the mirror. "Can't you give me more time to get here?"

As Sofia was ready, a sapphire blue book magically flew down into Sofia's hands, knocking her into the chair. Sofia was surprised that the story she has to complete is...

"The Tale of the Sapphire Snake?" Sofia read the title. "I wonder what that snake is up to."

The book flew into the mirror, and Sofia listened to the story carefully.

There was a beautiful kingdom where a wonderful royal family lived: the kingdom of Albuquerque.

"That's Hugo's kingdom," Sofia smiled. She knew this story had to do with her best friend since the Sapphire Snake lived in his kingdom. Sofia listened to the rest of the story.

The Sapphire Snake used to steal gold and jewels from the people of the kingdom, so King Garrick asked his royal sorcerer to cast a spell that allowed him to reason with the Snake. The king and queen offered the reptile 10,000 pieces of treasure if he would stay in his den, and since then, the kingdom has been safe.

Thanks to all the treasure, the Sapphire Snake has stayed in his den for years. But one day, for reasons unknown, the Snake escaped from his den and is roaming the kingdom. King Garrick has sent his sons to assist their new knight, Sir Oliver, to stop the Snake, but the mission does not seem to be going too well for the princes.

Sofia was horrified. She has finished many stories with plot twists, and she knew this story had to have one for sure. Sofia had a run-in with Sir Oliver before. She remember having to finish The Tale of the Noble Knight, Sir Oliver was believed to be the Noble Knight of Brazendell, especially when he volunteered to stop the dragons because they were setting fires. But when Sofia first met him, he turned out to be arrogant and rude. Sofia found out later that Sir Oliver had been trying to drive away the dragons and making them set fires, so that he can stop them with the Ice Fire Shield and look like a big hero...and all because he wanted the King of Brazendell to name him First Knight. Once Sofia and Sir Jaxon (the real Noble Knight) stopped Oliver, they exposed his deception, and Oliver was banished from Brazendell.

"Sir Oliver is going to stop the Sapphire Snake?" Sofia gasped. "Oh, he's up to something! I've got to stop Sir Oliver and warn Hugo before it's too late!"

Sofia hurried out of the Library and went to get her flying horse Minimus.