Lisa Cortes’s documentary is an irresistible tribute to the pioneering rock’n’roll genius, whose wild transgressive energy and explosive sexuality blazed a trail and created a musical and performing language for James Brown, the Beatles, the Rolling Stones, Prince, Elton John, David Bowie, and many other stars – some of whom had the good grace to thank him.

And he is now considered a great queer artist, which is how many interviewees here describe him; Little Richard in fact described himself as gay, and the movie perhaps could have done more analytical work in thinking about the relationship between the two terms. But it certainly does an excellent job at pointing out the hiding-in-plain-sight outrageousness.

Tutti Frutti (an inspired title which hints at an ice-cream flavour while also meaning “all fruits”) was originally about anal sex, the lyrics being: “Tutti frutti, good booty / If it don’t fit, don’t force it / You can grease it, make it easy”. The wacky verbal inventions like “Awopbopaloobopalopbamboom!” for Little Richard’s recorded version are a tactful, inspired soundscape version of the act itself. But even un-coded, the lyrics like “Good golly, Miss Molly sure like to ball!” … well, what did we think that meant?

Little Richard was always remarkably tolerant and good-natured, even when white artists did inferior cover versions of his material; these include Elvis Presley, but also, incredibly and toe-curlingly, Pat Boone, whose excruciating travesties sold better than the original. Cortes talks about the artists that came before Little Richard, from whom he drew inspiration for his music and his exuberant pompadour (which in later years became a wig): Billy Wright, Eskew “Esquerita” Reeder and also the amazing Sister Rosetta Tharpe.

Little Richard emerges here as an exquisite figure, an aesthete and athlete: a butterfly who could never be broken on any wheel.

• Little Richard: I Am Everything is released on 28 April in UK and Irish cinemas.