The show follows the adventures of a young boy named Ken, who has always dreamed of owning a car, and Bumpety Boo, a talking yellow car who hatched from an egg in the first episode, as they travel the world in search for Bumpety Boo's mother. Bumpety Boo, the fun-loving car, makes friends with Ken. Teaming up seems like a natural thing, but Bumpety Boo doesn't count on Ken's adventurous eight year-old spirit. Throughout the series, Dr. Monkey tries to steal Bumpety Boo from Ken.
During their expedition they have great adventures, and help a lot of people they encounter on their way. They also encounter other talking cars. Bumpety Boo usually races them and always wins because of his strength and speed, which he receives after he smells flowers. In the end of the series the group finds his mother.