Think Turandot or Lulu. Arnold Schoenberg lived on for many years with two acts of Moses und Aron finished, but the third act he had planned never became a reality. He did not allow for performances of his incomplete opera, and so it was only shortly before his death that Moses und Aron was first performed. In the decades since then, this harsh but fascinating work has made it to the stage of most of the world’s great opera houses…and festivals.

The Ruhrtriennale is an arts festival in Germany, and Willy Decker has led it since 2009. His staging of Moses und Aron was filmed in 2009, and the DVD preserves a scintillating performance, well outside the bounds of standard operatic performance. The only criticism of the DVD package is that there is no bonus feature on the production, and that is a keen disappointment not just because such features have become ubiquitous. Generally they are only modestly enlightening, if even that, but after viewing this production, many a viewer is likely to want to hear more - from the director, musicians and performers - as to the experience just seen. At least the modest booklet offers the director’s thoughts (translated into English by Stewart Spencer). Decker basically provides a detailed synopsis that probes the psychological reality of the libretto’s action. Then in his last paragraph, Decker finds in the unfinished state of the opera a metaphor for the work’s themes: “Schoenberg…equated his own inevitable failure with the tragic failure of his eponymous hero Moses…”

The performing area is unorthodox. The audience sits in two bleacher-like sections, facing each other, and the orchestra is off to one side. At key moments the bleachers pull apart to create a performing space. Sometimes a scrim-walled box descends from the rafters. At other times, one side of the theater, opposite the orchestra, opens for entrances and exits. The contemporary costumes of Wolfgang Gussmann and Susana Mendoza come in shades of gray and black. Instead of suggesting a specific time, however, they help to create a sense of timelessness, which makes the action both metaphorically consistent with the libretto’s narrative and evocative of its universal themes.

Decker has always been a master of theatrical movement, a very real rarity in the world of opera. Anyone who has seen Decker’s Salzburg Traviata should know that. His work here with the chorus, let along the leads, is phenomenal. The sense of a lost people, torn in their allegiance, prey to the more ferocious impulses of human weakness, makes for a stage orgy that is not risible - a notable achievement in itself.

Dale Duesing as Moses and Andreas Conrad as Aron live every moment, some of which must have been physically arduous. Their vocalism is unimpaired, thanks to being projected through small microphones. Michael Boder leads the Bochumer Symphoniker in a reading that makes the sheer aggression of the score an adrenaline rush, a bravura demonstration of orchestral power. No, no one will leave humming any tunes, but Schoenberg’s sound world leaves its own impression, one of force and honesty.

At around 100 minutes, the sheer intensity of the performance almost becomes exhausting. Perhaps with a completed third act, Moses und Aron would simply be too brutal an experience. Someone may yet attempt a completion, as was done for Berg’s Lulu. But even if successful, a completed version won’t eclipse the achievement of Willy Decker and company in this remarkable DVD.

Chris Mullins