In Tinker Bell and the Lost Treasure, Tinker Bell is tasked with creating a special scepter to hold the magical moonstone that will restore the Pixie Dust Tree. However, just before the blue harvest moon rises, Tinker Bell accidentally breaks the scepter and the moonstone shatters into hundreds of pieces. Without the moonstone, the Pixie Dust Tree begins to die, and it's up to Tinker Bell to fix her mistake.
Tinker Bell embarks on a dangerous journey to find the pieces of the moonstone, accompanied by her friend Terence. Along the way, they face many obstacles, including an angry octopus and a swarm of bats. They also meet new fairy friends, including Blaze, who helps them navigate a treacherous lava-filled cave.
As the time for the blue harvest moon approaches, Tinker Bell struggles to find all the pieces of the moonstone. She begins to lose hope until she meets a wise old owl who helps her realize that the pieces are not lost, but rather scattered throughout Pixie Hollow, waiting to be discovered.
With this new understanding, Tinker Bell and her friends race against the clock to gather all the pieces of the moonstone before it's too late. In the end, they succeed, and the Pixie Dust Tree is restored, allowing the fairies to continue spreading magic throughout the world.