In 1992 Dag Freyer and the late Syrthos J Dreher set out to make a film about Arturo Benedetti Michelangeli. They pursued the reclusive pianist to no avail, yet managed to shoot behind-the-scenes footage of the production crew preparing to document his 1992 Munich performance of Ravel’s G major Concerto. Given the pianist’s reputation for perfectionism and tendency to cancel more concerts than he actually played, everyone involved appears to be on tenterhooks. Afterwards, the pianist orders the recording destroyed, apparently due to a lighting mishap.

After Michelangeli’s death in 1995, the film-makers continued their journey, tracking down the pianist’s friends, colleagues and associates, along with rare rehearsal and concert recordings. The resulting film may not completely penetrate the Michelangeli mystique, yet it opens up more than a few windows. Angelo Fabbrini, for example, had to be as much a psychologist as a piano technician when dealing with Michelangeli’s flare-ups. At the same time, Fabbrini recalled how the pianist’s hypersensitive touch led to the discovery of a minuscule imperfection in a single hammer. Having served as Michelangeli’s record producer between 1975 and 1990, Cord Garben offers the film’s most extensive personal and artistic insights. He analyses the pianist’s remarkable technical abilities and physical attributes, if not entirely warming to certain interpretations. He pinpoints the central episode of Chopin’s Op 33 No 4 Mazurka as a magical moment, where Michelangeli seemingly suspends the tempo: it’s not what Chopin writes, yet the effect is ‘sensational’.

After mulling over possible collaborators for an upcoming Mozart concerto project, Michelangeli insisted that Garben himself conduct. Footage from the rehearsals shows the pianist dominating the proceedings rather impatiently, together with casual, ruminative moments alone at the keyboard. By contrast, Countess Marcella di Pontello remembers the younger, less austere Michelangeli as her frequent house guest, regaling her with Rhapsody in Blue.

The key to Michelangeli’s artistry, of course, lies in the musical examples. Only one work appears in its entirety: the enigmatic unison finale of Chopin’s Piano Sonata No 2, filmed at the 1967 Salzburg Festival. Michelangeli’s fusion of speed, equilibrium and sheer evenness makes one wonder about the three earlier movements from the same source. Other rarities include a snippet of ‘Le gibet’ from Ravel’s Gaspard de la nuit filmed at La Grange de Meslay, and a breathtaking Scarlatti excerpt from 1949. We also hear the audience tape that preserves the most harrowing moment of Michelangeli’s performing career, when he suffered an aortic aneurism in the middle of Debussy’s ‘Ondine’ during his Bordeaux recital of October 17, 1988. It’s rather eerie yet oddly moving to experience Michelangeli stopping in mid-air, then quietly calling out for help, as if the myth had momentarily shed his impenetrable mask.