Dave Davies

Medical historian and surgeon Ira Rutkow points to physical evidence that suggests Stone Age people conducted — and survived — brain surgery. We talk about the evolution of surgery from ancient societies to robotic surgery today. His new book is Empire of the Scalpel.

Waterston joined the cast of the original NBC series in 1994 on a one-year contract. He wound up staying 16 years, until the series wrapped in 2010. Now the show's back — and so is he. We talk about working into his 80s, Grace and Frankie, and how the 1984 film The Killing Fields changed his life and career.

Dr. Farmer worked to improve health care in the developing world. He died in Rwanda Feb. 21, on the grounds of a hospital and university he helped establish. Originally broadcast in 2011.