Theo the Snail lives and works in a tomato garden with his brother Chet.
Theo's obsession with speed compels his to go on a dangerous journey from the garden gets him sucked into a drag race. When he gets sucked into a teenagers nitro boosted car and undergoes a miraculous transformation.
He is picked up by a taco salesman named Tito and put into a snail race, where his magical powers soon become apparent. Tito, with the help of some friends, decides to enter Turbo in the Indy 500, where the snail has to compete against his long-time idol, the race car driver Guy Gagné.
Gagné becomes Turbo’s antagonist, and in their great struggle for the Indy win Turbo nearly dies, losing his magic powers in the process
With the encouragement of his friends, Turbo makes one last giant effort, crawls across the finish line, and wins the race by a finger’s length
He then returns from his adventure with the ability to help his fellow men and snails at Tito’s taco stand and the shops of his friends who have helped them in this quest experience a tremendous boost to their business because of Turbo’s fame, and the snails in the garden are forever safe from danger