In a special presentation of the sixth season, America's top gumshoes prove once again that an object found in an attic or backyard might be anything but ordinary. Wes Cowan, independent appraiser and auctioneer; Gwendolyn Wright, professor of architecture, Columbia University; Elyse Luray, independent appraiser and expert in art history; and Tukufu Zuberi, professor of sociology and the director of the Center for Africana Studies at the University of Pennsylvania, leave no stone unturned as they travel around the country to explore the stories behind local folklore, prominent figures and family legends. Slave Songbook - The president of the Mayme A. Clayton Library & Museum in Culver City, California, recently discovered an unusual book in his late mother's extraordinary collection of African-American artifacts. The small, cloth-bound book, titled Slave Songs of the United States, has a publication date of 1867 and contains a collection of 136 plantation songs. Could this be the first book of African-American spirituals ever published? HISTORY DETECTIVES host Wes Cowan visits a music historian in Los Angeles to explore the coded messages and the melodies that laid the foundation of modern blues, gospel and protest songs of future generations. He also meets with Washington, DC's Howard University Choir for a special concert of selections from Slave Songs sung in the traditional style of mid-1800s spirituals. Josh White Guitar - A Michigan man owns a Guild brand acoustic guitar that he says once belonged to legendary African-American folksinger Josh White, who is credited with introducing black folk, gospel and blues music to a world audience in the 1940s. The contributor met White after a concert when he was a kid, and the guitar reminds him of a confidence White had shared with him: the Guild Company was talking to White about making a signature guitar built to his specifications and marketed under his name. If this is the guitar White had spoken of, it would be the first signature guitar ever created for an African-American musician in the United States. HISTORY DETECTIVES host Elyse Luray travels around New York City and New Jersey to explore the crossover appeal of Josh White's music and his ability to win over a racially polarized music industry. Birthplace of Hip Hop - A hip hop enthusiast from New York City has always heard that 1520 Sedgwick Avenue in the Bronx is the birthplace of hip-hop. The story goes that on August 11, 1973, DJ Kool Herc, a building resident, was entertaining at his sister's back- to-school party and tried something new on the turntable: he extended an instrumental beat (breaking or scratching) to let people dance longer (breakdancing) and began MC'ing (rapping) during the extended breakdancing. This, the contributor believes, marked the birth of hip-hop. The music led to an entire cultural movement that's altered generational thinking - from politics and race to art and language. HISTORY DETECTIVES host Tukufu Zuberi sets out to examine an inner-city environment that helped lay the foundation for a cultural revolution.