When a mischievous little racing car called Ace passes through Sodor on his way around the world, Thomas is inspired to embark on his own ambitious trip. Traveling full steam ahead across five continents, Thomas discovers magnificent new sights and experiences exciting places and cultures. Along the way, he makes friends with a fun Kenyan engine called Nia. With so much for Thomas to learn about the world, will Nia be successful in teaching him a lesson about the true meaning of friendship?