Father Joseph T. O'Callahan was the first military chaplain to receive the Medal of Honor. An unlikely war hero, the bespectacled math professor who became the U.S. Navy’s first Jesuit chaplain, served in combat in both the Atlantic and Pacific theaters. He was on board the USS Franklin, an aircraft carrier known as Big Ben, in the Okinawa campaign in early 1945 when a kamikaze attack nearly destroyed the ship and killed hundreds of sailors. As the Franklin lay dead in the water, consumed by flames and drifting toward Japan, the chaplain organized fire-fighting crews and ministered to the injured and dying. The carrier’s captain called Father Joe the bravest man he ever knew. To document the Franklin’s ordeal and the chaplain’s actions, the author draws on interviews with survivors and O'Callahan’s family and many unpublished sources.