Bev Bevan explores the origins of heavy metal music and Black Sabbath's homecoming gig, with interviews and music from Black Sabbath, Judas Priest and Slipknot. As the music stops, fireworks go off above Villa Park as the founders of heavy metal bow out of their unbelievable career.

Reuniting onstage for the first time in two decades, Black Sabbath performed to a sold-out crowd of 40,000 with its all-star, one-day-only charity festival Back to the Beginning, held in Ozzy Osbourne’s hometown of Birmingham on July 5 and serving as a farewell concert to and celebration of the longtime rocker.