Wizbo is the name given to the mechanical rabbit that greyhounds chase at Chimdale Park in "Fleabiscuit".
Klaus, feeling that the mechanical rabbit is too plain looking, sets out to give it a little more personality and ends up going for a wild ride and becomes hooked on staying just out of the dog's reach.
Hayley, feeling pushed aside after Jeff's dog Fleabiscuit wins the first leg of the Triple Crown, teams up with Roger who adopts the persona of a greyhound named Ryan. Together with Klaus who rides Wizbo and taunts Roger along the way to run faster, resulting in his quickly climbing the ranks in order to face Fleabiscuit in the final race.
When Jeff learns of this, he accuses Hayley of being jealous of his success and becomes even more determined to win. However, Roger demoralizes Fleabiscuit, and during the big race, he refuses to run. Hayley realizes she's about to break Jeff's heart so she stops Wizbo for a distraction, leaving both Klaus and the rabbit to get mauled by the dogs.