When Alfa Romeo fired Enzo Ferrari in 1939, the "Commendatore" received a generous severance payment, but he lacked a new goal, especially as he was not allowed to design racing cars under his own name. Enzo Ferrari elegantly circumvented this restriction and built a sports car for two motorcycle racers to take part in the 1940 Mille Miglia. One of these two Auto Avio Costruzioni Tipo 815 survived and its story is told here and illustrated with historical pictures.