Tinker Bell (Mae Whitman) is born from the first laugh of a baby, and is brought by the winds to Pixie Hollow (which is part of the island of Never Land). She learns that her talent is to be one of the tinkers, the fairies who make and fix things. Two other tinker fairies, Bobble (Rob Paulsen) and Clank (Jeff Bennett), teach her their craft, and tell her about the fairies who visit the mainland to bring each season. Tink is thrilled and can’t wait to go to the mainland for spring.
While out working, she meets Silvermist (Lucy Liu), a water fairy; Rosetta (Kristin Chenoweth), a garden fairy; Iridessa (Raven-Symoné), a light fairy; and Fawn (America Ferrera), an animal fairy. After meeting them, she notices Vidia (Pamela Adlon), a fast-flying fairy who immediately dislikes her because of her unusually strong talent. Vidia challenges her to prove she’ll be able to go to the mainland, and Tink creates several inventions out of Lost Things (to which some other fairies see as junk) that she found on the beach, which she shows to the Minister of Spring (Steve Valentine). But Tinker Bell soon learns from Queen Clarion (Anjelica Huston) that only nature-talent fairies visit the mainland.
Desperate to help change the seasons in the mainland, Tink tries her hand at nature skills—making dewdrops with Silvermist, lighting fireflies with Iridessa, and trying with Fawn to teach baby birds to fly but she fails miserably at all of these. Meanwhile, Bobble and Clank cover for Tink when questioned by Fairy Mary (Jane Horrocks), the tinker fairy overseer. When Tinker Bell returns, she tries to explain, but Mary simply responds that she knows, and expresses her disappointment with Tink’s actions.
On the beach, Tinker Bell finds parts of a music box and figures out how to put them together. Iridessa, Fawn, Silvermist, and Rosetta witness her doing this, then tell her that she was tinkering and that she should be proud of her talent—if this is what she’s good at, the mainland shouldn’t matter. But Tinker Bell still wants to go to the mainland. She asks Rosetta if she’ll still teach her to be a garden fairy, but Rosetta says that tinkering is Tinker Bell’s natural talent.
As a last resort, Tinker Bell asks Vidia for help in becoming a garden fairy. Vidia craftily tells her that capturing the sprinting thistles would prove her worth. However, once she sees Tink making progress, she lets the captured thistles loose, and in attempting to recapture them, Tink destroys all the preparations for spring. After seeing the descruction she caused, Tink decides to run, but after talking with the dust-keeper Terence (Jesse McCartney) about how important his job is, she realizes the importance of a tinker.
Tinker Bell redeems herself by using Lost Things to invent machines that quicken the process of doing tedious tasks, such decorating flowers, painting bugs, planting seeds, etc. This allows the other fairies to get back on schedule, thus saving the arrival of spring. Vidia is punished for prompting her to cause the chaos, and Queen Clarion allows Tink to join the nature-talent fairies when they bring spring to the mainland. Tinker Bell is given the task of delivering the music box to its original owner (shown to be Wendy Darling). The narrator ends by saying that when lost toys are found or a broken clock starts to work, “it all means that one very special fairy might be near.”