USS Thresher- A contributor in Chicopee, Massachusetts, has a stack of technical drawings and engineering documents he found in his late great-uncle's basement some years ago. A few of the documents bear the numbers and letters SSN-593, an appellation that belonged to the nuclear submarine USS Thresher, an attack class vessel that had been the pride of the U.S. Navy during the Cold War. On April 10, 1963, the Thresher was undergoing deep-sea trials when, along with its nuclear reactor, the vessel and all hands sank 220 miles off the coast of Massachusetts. HISTORY DETECTIVES host Gwen Wright travels to New York, New Jersey and Massachusetts to explore one of the most traumatic events in U.S. Naval history and to determine just how the contributor's great-uncle could've come into possession of documents linked to one of the most secret weapons in the U.S. Cold War arsenal.

Pete Gray Cartoon - A comic book collector in Brooklyn, New York, owns several storyboards from a cartoon comic strip dating to the immediate post-World War II period. The strip relates the story of Pete Gray, the first one-armed major league baseball player, who later became an icon for disabled WWII veterans. The contributor is curious to learn the identity of the mystery cartoonist. Because many artists from the golden age of cartoons - the late 1930s through the 50s - often moonlighted in advertising or more "respectable" trades, their identities were often undisclosed. HISTORY DETECTIVES host Elyse Luray heads to Baltimore's Camden Yards and to comics hot spots in New York City to examine how cartoon artists helped reframe popular culture in the mid-20th century.
 
Manhattan Project Letter - A contributor in New York City has a scrapbook of typed and handwritten documents connected with the top-secret Manhattan Project, which developed the United States' first nuclear bombs during World War II. The most intriguing item is a letter dated just after the war. It's a plea for reduced secrecy regarding nuclear affairs in the scientific community once hostilities ended. Did the scientists' letter help persuade President Harry S. Truman to change policy in the post-war era? Host Wes Cowan leads HISTORY DETECTIVES to New York City to track down the authors of the documents and to explore the delicate balance between science, military power and democracy.