The Leonard Bernstein biopic opened last weekend on a limited release and to mixed reviews. Bradley Cooper acted the central role, directed and co-scripted the film. He was stretched thin at times.

Like most others who had personal experience of Bernstein, I was curious to see how closely Cooper simulated Lenny’s voice and mannerisms. The resemblance was, in a word, astonishing. Cooper was also masked up prosthetically to look enough like his character for us to suspend disbelief for the duration of the film. His imitative conducting, however, lacked traction. The musicians managed without looking up.

Carey Mulligan as Bernstein’s wife Felicia was empathetic and often moving, an obvious Oscar frontrunner. The comedian Sarah Silverman was brilliant as sister Shirley. Scott Ellis was unerringly creepy as Bernstein’s business manager Harry Kraut. The rest of the cast were flawless, and the period costumes were beyond nostalgic.

Cooper’s film centred on Bernstein’s double life as a homosexual and a married father of teenaged children. That was its core script — but this narrow focus occluded Bernstein’s musical significance and the foundations of his duality. In doing so, it distorted its own story.

His wife became integral to his public persona, essential for his respectability

Consider the background. In 1953, Leonard Bernstein was refused a passport renewal by the State Department on FBI accusations that he was a Communist sympathiser. Overnight, his world shrunk. Unable to conduct in Europe, he turned to US orchestras and often struggled to find work. The Boston Symphony, his hometown orchestra, had rejected him as music director. Unemployed and to some extent intimidated, he turned back to his 1940s pals on Broadway to create a pair of musicals, Candide and West Side Story. The second was box-office gold.

Bernstein’s popular appeal persuaded the New York Philharmonic to offer him its podium in 1957, initially in joint occupation with his mentor Dmitri Mitroupolos. The orchestra was not quite sure at first about Bernstein. As part of its publicity campaign, and to counter media whispers, the Philharmonic highlighted his happy domestic life with Felicia, whom he had married in 1951. She became integral to his public persona, essential for his respectability.

Bernstein revolutionised New York’s repertoire with injections of Mahler, Nielsen, Shostakovich and two dozen American composers. He launched Saturday morning televised talks for young people at Carnegie Hall, educating a whole American generation in the elements and excitements of orchestral music. He and Felicia were shining lights of New York society, equivalent in fame and glamour to the Kennedys in the White House. The film version of West Side Story carried his fame worldwide. He combined the roles of composer, conductor, teacher, social commentator and reformer — too much for one man, one life.

This context was entirely missed in Cooper’s film. Yes, Cooper proved it was possible to tell Bernstein’s story simply through the prism of his homosexuality. Ignoring the political and musical backdrop gave viewers little clue as to why they should care about his character, though. It reduced Maestro to just another empty two hours of formulaic movie-making.

Coming soon on Netflix.