This is a fascinating glimpse into the life of a pianist whose celebrity seemingly knew no bounds. Made eight years after Cliburn’s triumph in the inaugural 1958 Tchaikovsky Competition, it takes us, with intriguing diversions, through the daily life of an all-American hero. Here is Cliburn at Summer School, happy to talk to the students about his super-stardom, to play and conduct them through Prokofiev’s Third Concerto, requiring a ‘fat’ sound here and greater expressive intensity there (significant requests given his own famously full sonority and free-wheeling romanticism). The manner is charming and benign without a hint of the storm-clouds and disillusion to come, and with a huge capacity to sign autographs and beamingly recall the names of each adoring teenager.

The pianist’s mother, Rildia Bee, is omnipresent, recalling her son’s prodigy years when not listening critically and intently to his recording sessions. Clibern himself may be no great philosopher, but it is touching to hear him evoke the thrill of his early love of music and of its unique capacity to encourage spiritual awareness, focus and concentration.

There is footage of Cliburn talking to Kabalevsky, and performing Rachmaninov’s Second Concerto with Kirill Kondrashin (his partner in the 1958 Moscow triumph). There are shots of the pianist practising Liszt in his Arizona retreat and a quick flash of scales that says a great deal about his formidable mastery. Reconciling accuracy with freedom in the recording studio presents a frustrating conundrum and his disc of Chopin’s Second and Third Sonatas finds him agonising over a familiar dilemma (‘it’s perfect, but it doesn’t sound right’).

All this, then, before image became reality, when communicative ardour collapsed into lethargy and indifference. Engulfed in sensationalism, a warm-hearted if naive man was scarred by the prussic acid of commercial celebrity. Happy to trace his mother’s musical pedigree to Liszt, Cliburn, ironically, developed that composer’s unhappiness as a public performer. Liszt virtually retired from concert-giving at 36. Cliburn’s career, though longer, was similarly, and sadly, brief.