For the first time ever, the city of Ticswyk is hosting its very own airship race. The winner will receive a prize that any tinker would covet-the chance to have his or her airship mass-produced. Lionel is determined to win, spending night and day preparing the finest engine ever built. But his old nemesis, Jamison Morcroft, is skulking about, trying to steal the Master Tinker's design. Cali will stop at nothing to protect her dearest friend, even if it means facing down Morcroft himself. Determined to find out what he's up to, she risks her life investigating the evil man's schemes. With help from Emmit and a new canine pal, Gadget, the trio set out to keep Lionel, and his airship, safe from harm.