In 2012, scholar John Turner published an award-winning biography of Brigham Young, a mountain of a man in Western Americana. But there remained a bigger fish to pursue, namely Joseph Smith, the “white whale” of Mormon history, the religious icon who gave birth to The Church of Jesus Christ of Latter-day Saints.

Turner’s voyage is now complete and the resulting book, “Joseph Smith: The Rise and Fall of an American Prophet,” is available this month.

Infused with the latest scholarship, the volume reveals a Brother Joseph who is sometimes playful, sometimes reckless, sometimes incensed, often inspired, but always enterprising and forever fascinating.

The book appears certain to go down as the most significant and up-to-date biography of the Mormon founder since Richard Bushman’s “Rough Stone Rolling.”

On this week’s show, Turner, professor of religious studies and history at George Mason University, discusses what he discovered about Joseph Smith — the husband, the father, the book publisher, the community organizer, the city builder, the religious innovator, the polygamist, the visionary, and, above all, the prophet to millions of followers.