This spin-off takes place in a very different setting, where instead of the Mafia, Racers exist. Racers use go-karts, and during a race anything goes, including any type of interference to prevent your opponent from winning.
Tsuna is the descendant of the person know as the greatest racer in history, Primo, but is absolutely horrible in the sport himself and has lost 999 races in a row. Tsuna races for Team Vongola, and is known as the disgrace of Vongola Town. One day, a baby named Reborn suddenly appears in front of Tsuna and claims that he's been ordered by Vongola the Ninth to become Tsuna's racing coach and train him to become a great racer like Primo.