Tom Slick, upstanding competitor and all around good sport, took part in racing events all over the globe, accompanied and cheered on by his girlfriend Marigold and the grandmotherly but sassy Gertie Growler (of unidentified acquaintance). He competed in a vehicle called the Thunderbolt Grease-Slapper, which he converted beyond recognition prior to every race to suit the conditions of the race: forming such unlikely vehicles as a submarine, hot air balloon, motorized skateboard, etc., in addition to all forms of standard road racer. Never far from the action, Marigold, and even Gertie, occasionally rode shotgun during the races.
In the racing world, Tom was a fan favorite, greeted by a cheer of enthusiasm whenever he was announced. His biggest supporter was Marigold, who was completely smitten with him, although Tom was wholly devoted to his sport and oblivious to her gestures of romance. Unfazed by Tom's inattention, Marigold interpreted his most humdrum of statements as signs of affection.
As if the normal dangers of racing weren't enough, Tom had to contend with at least one cheater and spoilsport in every competition. His most frequent opponent (in fact, the only opponent who appeared in more than one episode) was Baron Otto Matic and his simple-minded henchman Clutcher. Tom Slick's unwavering optimism and resourcefulness in the face of adversity (with an occasional timely assist by Marigold and Gertie) insured that the Baron was no more successful in carrying out his dirty tricks than any of the other competitors. Whenever his plans went awry, or just for good measure, the Baron reinforced his bad guy status by clobbering Clutcher with a wrench, whether or not any fault lay with Clutcher.
Despite obstacles thrown in his path by the machinations of rival racers, Tom managed at the last moment to win every race he entered, making him perhaps the most successful racer in the history of the sport.