According to the publisher of this DVD, ICA Classics:
Filmed in colour from Canterbury Cathedral in 1968, this DVD represents the only existing film of Sir Adrian Boult conducting The Dream of Gerontius.
Sir Adrian Boult championed Elgar’s music throughout his life, following the composer’s prophetic words in a letter to the conductor: ‘I feel that my reputation in the future is safe in your hands’.
Featuring a stellar cast of soloists including Dame Janet Baker, this performance is redolent of Sir Adrian Boult’s ‘commendable energy and typical humanity’ (The Gramophone Guide review of Boult’s 1975 studio recording of The Dream of Gerontius).
This DVD also features a 60-minute documentary on Sir Adrian Boult produced by the BBC in 1989 to celebrate the centenary of his birth.
This review offers some background to the production of the broadcast:
You can find the performance online but the version posted is from a VHS tape. I think I have enough CD versions of Elgar's Dream so this is not on my wish list. I can't help, however, from pointing out that this is the story of a man dying, facing his personal judgment, and going to purgatory. It's being performed in what was once a Catholic church where people came on pilgrimage to expiate their sins and pray for the Poor Souls in purgatory--which is now an Anglican cathedral. I wonder if there was any backlash at the time against a Catholic work by a Catholic composer based upon the poetry of Catholic convert from Anglicanism being performed in the primary see of the Anglican Church, which eliminated prayer for the dead and denied the reality--and the hope--of purgatory?