Two friends, Arnie the mouse and Bill the sparrow, decide to build a car together. They enjoy the invaluable help of Christian the frog, who can provide them with all the necessary parts – so the team can work happily. Our characters are neither angels nor stars of the animal kingdom. The two friends live on the outskirts of a city, among old yards, auto repair shops, and near a large car dump. In this world, cleverness and irony are common themes.

As the story progresses and Arnie with his friends faces many difficulties that complicate their task, the reader will learn how to assemble a car and how it works. Reading this book will help in understanding the mechanics of engines, clutches, brakes, distributors, and many other car components.