Nineteen-year old Dick Kennedy comes to Detroit, lives in a boarding-house and gets a job in one of the enormous automobile factories. He is a determined, able boy and gets advanced pretty fact which gives the author a chance to tell about several different departments which will be fascinating to boys. He gets his recreation playing football, where he learns even more of the coordination and teamwork so important on the assembly line. In 1940 the factory expands to make tanks, all is speeded up, there is too much loose talk and finally Dick is embroiled in foiling a master saboteur. A good yarn for the present day.