Twin Spirits sets out to tell the oft-told story of the relationship between Robert and Clara Schumann, one of classical music’s great love affairs. John Caird’s entertainment, first staged at the Royal Opera House in 2005 as a charity fund-raiser, was recorded in front of a small audience in a studio space at the ROH in December 2007. All the artists involved donated their services free, and everyone buying a copy of the DVD will be supporting the work of the Opera House’s Education Programme.

Sir Derek Jacobi is the narrator; Sting and Trudie Styler (aka Mrs Sting) read from the letters between Robert and Clara; the musicians intersperse the text with music by Robert, Clara, Chopin and Mozart. Despite the best intentions of everyone, it proves an enervating experience on film. Sting’s hope that it will provide “a great introduction for people who don’t normally listen to classical music” is sadly optimistic: the unrelieved solemnity of the occasion and reverential text, filmed in a matching sepulchral gloom, are unlikely to inspire anyone coming anew to classical music. Indeed, it will confirm their worst fears.

Twin Spirits might fare better on radio: no one moves at all during proceedings. Sir Derek reads his script from the depths of an upstage throne; Sting and Miss Styler – the two lovers – are sat on opposite sides of the stage and thus never physically contact one another. Sting brings his charismatic presence to the composer; vocally and facially, Miss Styler is a one-dimensional Clara. The musicians, often perversely playing arrangements of Robert’s solo piano works, are dutiful rather than inspired (the exception being Keenlyside’s magnificent rendering of “Ich grolle nicht”). It is all bum-numbingly somnolent.

If you really want to find out about the Schumanns, musicologist Daniel Gallagher has some interesting insights in conversation with the director and cast on disc 2. Best of all is Dr Gerd Neuhaus from the Schumann Museum in Zwickau who talks about Robert and Clara without pause for 36 minutes, though it is in German and you have to be a quick reader to scan the non-stop subtitles. “Schumann,” he stresses, “is inconceivable without Clara…one heart and one soul – they cannot be separated.” Twin Spirits in life but, alas, not on stage.