In this episode, we will learn about the famous cardiac surgeon Dr. Alfred Blalock, and his famous work on blue babies suffering from Tetralogy of Fallot. But maybe of even greater interest is the story of his lab assistant, Vivien Thomas, a man without formal medical training but who collaborated with Blalock, helping him to develop his surgical breakthroughs. He received little credit at the time, but is now held in high esteem at Johns Hopkins.