In this instalment of the Perspectives documentary strand, journalist and occasional comic John Sergeant embarks on an immersive personal journey into the influence of Spike Milligan on his life, and on the nation's psyche.

Marking the year of the tenth anniversary of the comic legend's death, this 60-minute documentary shows John telling the story of how Spike not only created 'alternative comedy' in Britain but defined the modern British sense of humour using archive footage and interviews with stars of today.

Along the way, John meets household names of entertainment and comedy in his search to find the ultimate impact of Spike on the comedy landscape of Britain today.

Ultimately, he discovers that Spike's surrealist comedic influence stretches from Monty Python to Eddie Izzard and Noel Fielding, and still has the power to entertain youngsters today.

John starts by visiting his childhood home, a sleepy vicarage, in which he listened Spike's Goon Show as a child in the 1950s, and it meant everything to him. Later it inspired him to take up comedy writing and performance when he was at Oxford University.

"Spike Milligan means a lot to me, because my first job was as a comedian, not anything like as good as him, but as a comic actor with Alan Bennett. I can't imagine a comedian in Britain who doesn't acknowledge their debt to Spike Milligan. He inspired a generation."

He speaks with Spike's brother Desmond, who tells him by phone from Australia that Spike may have gained some of his wit and humour from his father, an entertainer in the Forces.

"He wasn't as zany as Spike, Spike was unique. None of us was quite as mad as he was."

He sits down to listen to extracts from The Goon Show with Eddie Izzard, who once described Spike as 'the godfather of alternative comedy', and explained that his impact on the comedians who followed was profound.

"Without Spike doing surreal, I wouldn't have existed. I don't think [Monty] Python would have existed."

After Spike's family were forced to come to England from colonial India, John discovers he took up work as a trumpeter in London clubs. He muses that some of his talent must have come from being an outsider, a 'million miles' from the comedians of the 1930s.

John visits the pub in Westminster, formerly the Grafton Arms, above which The Goon Show germinated and Spike lived with the landlord's monkey. He speaks with the landlord's children, who tell him Spike was a very funny man - until they grew older, which leads John to a revelation.

"What is happening here is we are catching Spike in his 30s, relating to children, and of course that's what he did at his best throughout his life as a comic."

As The Goon Show, also featuring Peter Sellers and Harry Secombe, grew to run for nine years, dominating the airwaves with more than 200 episodes, Spike's fame grew, before he was cajoled into making a short film.

John meets Esther Rantzen, who used to watch the show being recorded at a theatre in Camden. He also meets with John Antrobus, a playwright with whom Spike wrote, who describes the comic as a 'genius'.

He also visits comedian Noel Fielding, who praises the freeform surrealism of Spike's work and his ability to simply write comedy.

"Milligan was writing it, and that is the most impressive thing to me, to be able to write a lot. He was a bit mad, I mean that's what happens, you start looking for everything to be a joke in every situation and you sort of force your brain, when you are writing, to look for this humour or these abstract thoughts and sometimes you can't turn that off."

John visits Spike's former secretary Norma Farnes, who holds a treasure trove of Milligan minutiae. She describes him as a man who was prone to dark moods, which might last for days. She lets him see some home movies from his three weddings, and speculates as to what it might have been like to be married to Spike.

"I would think impossible, can you imagine being married to Spike Milligan? Must have been a nightmare."

Spike's career in television was by the 1970s being hampered by the comedians he had influenced in the 1950s, John discovers. One such comedian was Michael Palin of Monty Python, who paid tribute to Spike's influence.

"He did feel there was a bit of plagiarism going on. There was a slight bit of a difficult atmosphere. Spike could be one thing one day and say you were wonderful, and then the other 'all my best jokes, it's me, I did all this ages ago'. Which is of course true but I think we were flattering him in a way."

John then visits a school to see if Spike's comedy had the same impact now as it did on him. After a few minutes of hearing The Goon Show, laughter is abundant in the classroom, which leads John to a conclusion.

"So, after my voyage around the moon with members of Spike Milligan's fan club of all shapes and sizes what is my conclusion? It is simply that directly or indirectly he has affected us all, or as he might put it, 'infected' us all."