The author of a new biography on Spike Milligan talks to BBC News Online about his portrait of the contradictory comedy legend.
Spike Milligan's paralysing bouts of depression are well-documented - and now we learn in detail just how difficult he could be to live and work with.
Humphrey Carpenter's biography unravels the conflicting sides of this complicated man.
On one hand it paints Milligan as a bitter, resentful and sometimes violent individual who was also a racist and a womaniser.
Milligan's emotional lows were the source of his creativity
At other times, it says, he could be the most gentle and loving of souls - devoted to his children and a passionate advocate of animal rights.
In his book, Carpenter sets out to show that the depressions that so debilitated Milligan were also the sparks that ignited his comedy brilliance.
"The periods when he was at his lowest were matched by periods of high creativity," the author told BBC News Online.
"He was described as being like this incredible spinning top, whirring away until he slowed down and stopped."
Terence Milligan - he was nicknamed Spike by army mates - was born in 1918 in Ahmadnagar, India, of Irish descent, the son of an army sergeant.
Carpenter argues that Milligan was never the same after leaving behind his idyllic childhood on the sub-continent for drab pre-war England at the age of 15.
He envied the later success of fellow Goons Sellers and Secombe
He found England dreary and longed to return to the bright sunshine and clear skies of his childhood.
Failing to achieve this, the popular theory goes, he remained a boy in heart and mind throughout his life.
"Psychiatrists who treated him and got to know him well agreed that this was the time he retreated into childhood," said Carpenter.
The birth of his brother Desmond when Milligan was seven had a further significant impact on his fragile psyche.
"People underestimate the power of sibling rivalry," said Carpenter.
He harboured anger but could also be gentle-natured
"I think Spike was very fond of his younger brother but he undoubtedly got enormous care and attention for seven years. There's no doubt he was pretty spoilt."
An emotionally unstable mother also shaped Milligan's wayward adult character, says Carpenter.
But it was his experience of a wartime shelling as a soldier in 1941 that had probably the single most impact on his well-being.
A mortar bomb blew up just above his head, leaving him traumatised and triggering off his lifelong battle with manic depression.
The pressures of combat had also freed his inhibitions, leading to bursts of unstoppable creativity - although Milligan said he would have happily given up his career to escape the illness.
The madness he had encountered during war informed The Goons, his anarchic 1950s radio show also featuring Peter Sellers and Harry Secombe, which changed the face of British comedy.
He had a racist side - yet could get sentimental about animals
According to Carpenter, himself a BBC broadcaster, Milligan harboured anger and hatred towards others throughout his life, sometimes spilling over into violence.
He once threatened to stab Peter Sellers with a potato peeler, and was conditionally discharged for shooting a 15-year-old boy with an airgun for intruding in his garden.
"It may have been only an airgun pellet, but how many of us would even think about doing such a thing?"
There are stories of Milligan apparently attempting suicide, although Carpenter suggests these may have been attention-seeking stunts.
"There is evidence that he did it when he was bound to be caught."
The author also charges that Milligan grew up in India believing he belonged to a "superior" race, and later made no secret of his hostility towards ethnic minorities.
He sought many forms of artistic expression
He used racist language and performed anti-Semitic material well into the 1980s, Carpenter says.
"There was this strong element of racism which was unnecessary and makes me uncomfortable."
Further, he bore grudges about the career successes of fellow Goons Sellers and Secombe, and felt never had the recognition he deserved.
"He was certainly envious of them, if not jealous, and at this time he was getting some pretty awful scripts."
Married three times, he fathered six children and was "serially unfaithful" - although he was less interested in the act of sex itself than the conquest.
"Maybe this is where he was more 'normal' like many other people - I mean, why do people have affairs?"
In contrast to the darker side of his nature, Milligan is presented as a sensitive and prolific artist who turned out volumes of dazzling poetry and memoirs, had an instinctive feel for his beloved jazz, and steered a hugely innovative - if inconsistent - BBC comedy career.
He came to hate the description 'tormented genius'
"Some of his later work didn't always stand up, but he was always searching for new ways to express himself," said Carpenter.
The warmer side of his nature is best exemplified by him writing miniature letters for his children, supposedly from fairies, and leaving them to be found in his garden.
But few buy a biography to read about a nice guy. It is the mechanics of Milligan's "tormented genius" - a description of himself he came to hate - that engrosses and enlightens.
Spike Milligan: The Biography by Humphrey Carpenter is published by Hodder & Stoughton, priced £20.