"Bakusō Kyōdai Let's & Go!!" is a sports anime centered around the world of mini 4WD racing, a hobby where participants build and race small, battery-powered model cars. The story revolves around two brothers, Retsu and Go Seiba, who are introduced to mini 4WD racing by their father, a former racer. After their father's sudden passing, the brothers inherit his passion for the sport and decide to pursue it in his memory.

Retsu, the older brother, is calm and analytical, often focusing on the technical aspects of car building and racing. Go, the younger brother, is more impulsive and driven by instinct, relying on his natural talent and determination. Together, they form a strong team, complementing each other's strengths and weaknesses. The series follows their journey as they compete in various races, facing off against skilled opponents, each with their own unique racing styles and car designs.

The narrative is structured around their progression through different racing tournaments, starting from local competitions and eventually advancing to national and international levels. Along the way, they encounter a diverse cast of rivals, including J, a mysterious and highly skilled racer who becomes one of their most formidable opponents. Other notable characters include Tsuchiya, a passionate racer with a deep love for the sport, and Ishimatsu, a wealthy and arrogant racer who initially underestimates the brothers but later becomes a respected competitor.

The series emphasizes themes of perseverance, teamwork, and the importance of balancing technical skill with intuition. The brothers' journey is marked by challenges that test their resolve, from mechanical failures and intense rivalries to personal setbacks. Through their experiences, they learn valuable lessons about sportsmanship, friendship, and the joy of pursuing a shared passion.

As the story progresses, the brothers' bond strengthens, and they continue to refine their skills, both as racers and as individuals. The series culminates in high-stakes races where they must push their limits to achieve victory, not just for themselves, but to honor their father's legacy. "Bakusō Kyōdai Let's & Go!!" combines the excitement of competitive racing with heartfelt moments of personal growth, making it a compelling narrative for fans of sports anime.