TAKING STOCK’ For the Arditti Quartet’s CD recording of Helicopter, chopper sounds were overdubbed in studio.

One morning, the late Karlheinz Stockhausen awoke from a dream that told him to take to the sky. Stockhausen envisioned four helicopters swirling in the clouds, with each of a quartet’s members tucked inside his own chopper, communicating through headsets, stringing away in sync to the rotor-blade motors. He immediately set forth to make that dream a reality. In 1995, Dutch film director Scheffer followed Stockhausen in the days leading up to the premiere performance of his Helicopter String Quartet in Amsterdam. The resulting film offers a rare glimpse of Stockhausen as he patiently dictates every agonizingly detailed measure to the Arditti Quartet. “Not bad,” he grumbles with dissatisfaction in a rehearsal. “We are approaching…our…goal.”

The only composer on the cover of Sgt. Pepper’s, Stockhausen wrote the quartet as part of his 29-hour cycle of seven operas titled “Licht.” But labeling this music an “opera” was as close as he came to convention. In the film, when asked if this is his first string quartet, he reluctantly nods—and says it will be his last. With an indomitable spirit, Stockhausen never adhered to well-worn models, always preferring to invent his own.

Alternating comfortably between English and German, the composer stresses that his earlier works, such as Kontakte, Gesang der Jünglinge and Gruppen, were efforts to create “musical space around human beings.” The Helicopter String Quartet is no exception. When the motors kick on and the four helicopters finally ascend in the film’s climax, it recalls the Ride of the Valkyries sequence in Apocalypse Now—but with the string musicians in the helicopters. This engaging and excellent DVD is, at its heart, the story of a laughably absurdist vision powerfully realized.