Wire tapper: Clarke Peters uncovers the struggles of tap dance's black innovators

The Nicholas Brothers were among the best dancers of their era, and certainly the top duo during tap's golden age. Fred Astaire called their Jump Jive sequence in 1943's all-black film musical Stormy Weather, " the greatest movie musical number I've ever seen".

Compared to the majority of black entertainers of the time, the Nicholas Brothers were lucky and privileged. They appeared on Broadway and in a dozen movie musicals during the 1930s and '40s.

But, despite their relative status, industry segregation still relegated them to non-speaking parts and their dance sequences were often cut to mollify audiences in the American South. African American performers were routinely isolated from film plots to make this practice easier.

When African Americans were given speaking parts in films, it was in non-threatening roles like children, uncles or servants. The highest-earning black entertainer of the era was the great tap dancer Bill 'Bojangles' Robinson, whose four films as Shirley Temple's butler started when he was 56.

Another innovator, John Bubbles, the "father of rhythm tap", gave dance lessons to Fred Astaire and created the character Sportin' Life on Broadway in Gershwin's Porgy and Bess. In Hollywood, his act Buck and Bubbles would play college janitors in Varsity Show (1937).

The Nicholas Brothers were handsome, athletic young men who displayed a level of glamour and sex appeal that couldn't be tolerated in lead actor roles.

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Stormy Weather and another all-black musical from 1943, Cabin in the Sky, were part of a conscious effort by movie studios to attract African American audiences, who had more disposable cash than previously. These films were a chance for black performers to take lead roles.

Theatres in many cities refused to show the films. In Mt. Pleasant, Tennessee, Cabin in the Sky was pulled 30 minutes into the film - on orders from the local sheriff - after a hostile crowd gathered outside the theatre.

Stormy Weather marked the end of the Nicholas Brothers' contract with 20th Century Fox, which had been in place for two years - since Down Argentine Way. As tap expert Dr Constance Valis Hill tells Clarke Peters, "they were too mature, too dangerous, too threatening.”

The duo belatedly danced with a white star, Gene Kelly, when they reunited for their last Hollywood film together, The Pirate (1948), at Kelly's insistence. Their dialogue was cut by the studio from the final film, and their performance with Kelly was omitted from the reels shown in many southern theatres, for example in Memphis, Tennessee. At this stage in their career, essentially blackballed from major stardom, the brothers moved to Europe and toured there extensively as well as in Latin America and Africa.

It should have been a golden age for tap's most talented performers - when music, dance acts and the talkies met head-on in the movie theatres of America, and the tap dancing craze dominated Hollywood studio output. But tap's African American roots were sidelined, and a whole generation of performers saw their opportunities curtailed.

In the 1960s, aside from touring, the duo also taught master classes in tap as teachers-in-residence at Harvard University, and as Visiting Artists at Chicago dance school The Ruth Page Center for the Arts. Both Michael and Janet Jackson were later students of the brothers.

As well as Kelly and Astaire, the great ballet soloist Mikhail Baryshnikov was a huge fan, saying "they are probably the most amazing dancers I've seen. Those guys are perfect examples of pure genius".

As they are watching the Stormy Weather routine for the documentary, Dr Constance Valis Hill says to Clarke Peters , "we call this ‘class act dancing’ – they’re the epitome of the class act. Really bringing tap up from its shuffle roots, its slave roots, to the highest octave of sophistication and precision. They’re making the dance form modern, and a modern art form. I think that is really what pleases audiences."

Clarke responds, "What would have happened if they’d been allowed to continue in film, what kind of archive would they have had?" Hill: "Can you imagine!?"