Eton music scholar and cystic fibrosis suffer Alex Stobbs shot to international prominence in 2008 following the transmission of an award-winning documentary A Boy Called Alex. He has since become a choral scholar at King's College, Cambridge. This film features highlights from a remarkable performance of Bach's St Matthew Passion conducted by Alex at London's Cadogan Hall in 2009. Alex himself acts as the film's commentator and guide, offering his uniquely personal perspective on Bach's epic work and the phenomenal musical challenges in conducting it. The music is performed by the distinguished Southbank Sinfonia Orchestra and the renowned Rodolfus Choir, featuring soloists Michael Chance, Sarah Fox and Thomas Guthrie.