A heartless, self-indulgent, dead genius crying out for a biopic

If you didn't live through The Goon Show, you can have no idea what it meant to Britain in the 1950s, or how much it glorified Peter Sellers. It wasn't just the kind of radio programme that took off from the persona of some boisterous comic - Ted Ray, Arthur Askey, Max Miller. It was a sound world unto itself: infantile, conspiratorial, meticulous, utterly consistent and entirely reliant on the elastic voices of Harry Secombe, Spike Milligan, Peter Sellers and (until he fell foul of Sellers), Michael Bentine.

If you didn't live through The Goon Show, you can have no idea what it meant to Britain in the 1950s, or how much it glorified Peter Sellers. It wasn't just the kind of radio programme that took off from the persona of some boisterous comic - Ted Ray, Arthur Askey, Max Miller. It was a sound world unto itself: infantile, conspiratorial, meticulous, utterly consistent and entirely reliant on the elastic voices of Harry Secombe, Spike Milligan, Peter Sellers and (until he fell foul of Sellers), Michael Bentine.

Precocious schoolboys did Goon talk all day long (girls were helplessly left out). Teachers must have dreaded it - and, worse, slipping into it. For the Goons appealed to academics and the learned. They were the natural forerunners of Hancock's Half Hour, Kenneth Williams, Beyond the Fringe and Monty Python. And Peter Sellers was the show's genius.

By the late Fifties, as the radio show held strong, he had taken his plain looks into the movies and won another audience with a string of foolish comedies - The Naked Truth, Up The Creek, Carlton-Browne Of The FO, I'm All Right, Jack (where he played shop steward Fred Kite), The Battle Of The Sexes, Two-Way Stretch and The Millionairess, where he was an Indian doctor nearly inhaling Sophia Loren. That was another voice some of us couldn't get out of our heads. It was said that no one on earth made Prince Charles laugh as much.

Now, 20 years after his death (he was only 54), the National Film Theatre is offering a small Sellers season. Five films can't convey the man or his impact, not without tapes of The Goon Show murmuring in the bathrooms and the corridors. You need the succulent, privileged stupidity of Grytpype-Thinne, for one thing - Sellers' upper-class idiots were among the most subversive things in my, and Prince Charles's, childhoods.

Sellers was beloved in 1960, which may be a way of saying that no public had yet encountered the private man. In the twenty years left him, launched by two Stanley Kubrick films - Lolita (where he was Clare Quilty) and Dr Strangelove (where he was an RAF chappie, the US President and an evil genius) - he became an international figure. He made many of his movies in Hollywood, or with American money. He had a rash of marriages and girls; he was rich enough to do drugs and keep an entourage; and he became Peter Sellers of the heart attacks.

He had been cast to play the songwriter who trades his wife to a dissolute singer (Dean Martin) in Billy Wilder's scabrous Kiss Me, Stupid. But he was so difficult, so vain and noxious that when, in 1964, he had a series of heart attacks (so that he was replaced with Ray Walston), Wilder asked, out loud, how those attacks could be? How could a man without a heart have heart attacks?

For radio, Sellers had put all his soul into those voices. He was an impersonator par excellence, who wondered if he had a voice of his own. As he became famous, so he decided, consciously or not, to find himself in the depths of bad, unprofessional behaviour. He was manic-depressive; he was self-pity incarnate; he was hysterical, fickle and addicted to the occult. (Once, when told that a "BE" would be vital in his life, he met and married Britt Ekland - and then shortly thereafter bumped into Blake Edwards, director on the Pink Panther series.) He was also sometimes brilliant - although the Clouseau films turned into nightmarish productions, the early ones are often hilarious. And in Being There, he found his ideal role - the blank, empty Chauncey Gardiner who becomes presidential in his hollow celebrity.

No proper study of Sellers can manage without Roger Lewis's book, The Life and Death of Peter Sellers, one of the most aggressive yet penetrating accounts of a star's inner being. It is not a pretty read, and it makes clear how many movie projects Sellers ruined through self-indulgence. But Lewis's anger is prompted by the certainty that he had great talent. I read the book again for this column, and I realised that the life of Sellers would make a fine, macabre film - if only you could find the hollow shell to be Sellers. He could be so ingratiating, yet so cold and withering, and all the time there was the hint of a man preoccupied with vanishing.

The NFT season has The Ladykillers (1955), where Sellers is overshadowed by Alec Guinness, an actor who later obsessed Sellers, for Guinness had a famous lack of self that intrigued the comic; Never Let Go (1960), an oddity in which Sellers plays a sadistic racketeer who hounds Richard Todd - it doesn't work, but this was a first revelation of the darker side; The Pink Panther (1964), the original; Dr Strangelove (1964) - which I suspect looks rather hammy now, with Sellers not as naturally funny as George C Scott or Sterling Hayden; and Being There (1979), from the Jerzy Kosinski novel, and the classic portrait of Sellers close to death.

Who could play Sellers if they film his life? Well, he was very English, born in Southsea and raised in a touring theatrical company. Still, the actor who comes to my mind, a superb mimic, is Kevin Spacey, who could probably do English as well as Sellers could do you or me. Memo to Sam Mendes.