Trace Broadway’s early days, from the Ziegfeld Follies to the far-sighted masterpiece Show Boat.

When Florenz Ziegfeld Jr. first hits New York in 1893, the intersection of Broadway and 42nd is nobody’s idea of “the crossroads of the world.” But by 1913, “The Ziegfeld Follies really were an amalgamation of everything that was happening in America … at that time,” says writer Philip Furia. “Flo Ziegfeld was like the Broadway equivalent of the melting pot itself.” Ziegfeld’s story introduces many of the era’s key figures: Irving Berlin, a Russian immigrant who becomes the voice of assimilated America; entertainers, such as Jewish comedienne Fanny Brice and African-American Bert Williams, who become America’s first “crossover” artists; and the brash Irish-American George M. Cohan, whose song-and-dance routines embody the energy of Broadway. This is also the story of the onset of a world war and the Red Summer of 1919, when labor unrest sweeps the nation — and Broadway. The episode culminates in Ziegfeld’s 1927 production of Jerome Kern and Oscar Hammerstein II’s far-sighted masterpiece, Show Boat. “The history of the American musical theater is divided quite simply into two eras: everything before Show Boat, and everything after Show Boat,” says writer Miles Kreuger. With the Great Depression, the Ziegfeld era becomes a memory. The episode features interviews with Irving Berlin’s daughter Mary Ellen Barrett, Ziegfeld Follies girls Doris Eaton and Dana O’Connell, New Yorker critic Brendan Gill, theater artist Al Hirschfeld, composer/lyricist Stephen Sondheim and Ziegfeld’s daughter Patricia Z. Stephenson. Highlights include newly restored color footage of The Ziegfeld Follies and footage of Fanny Brice singing “My Man.”