As the cult of personality continues to dominate modern politics it seems a candidate who is passionate and articulate with the ability to stay the distance is a rare find. Alan Johnson has been representing the constituency of Hull West and Hessle since the Labour landslide in 1997 and is still as determined to obtain a fair deal for its community of trawler men and their families as he was at the beginning.

Alan talks about the battle to defend them and opens the door on the Houses of Parliament in the concluding book of his memoirs, The Long and Winding Road, in discussion with Brent North MP Barry Gardner at Chorleywood Litfest this weekend.

The book covers the period when Alan served as Home Secretary from June 2009 to May 2010 and homes in on the variety of cabinet positions he held in both the Blair and Brown governments, including Health Secretary and Education Secretary. Until 20 January 2011 he was Shadow Chancellor of the Exchequer.

His first book, This Boy, won the RSL Ondaatje prize and the Orwell Prize in 2013. His second, Please Mister Postman, won the National Book Award for Autobiography of the Year in 2014.

He tells me audiences are likely to have read these two previous instalments and may well be eager to see how he fares in the most challenging years of his career and how things turned out for him and his family.

“The first book was nothing to do with politics it was my life up until the age of 18 but it received not just critical acclaim but I am pleased to say it was a bestseller. Then the second one was about the period of the 70s what it was like bringing up three kids on a council estate in Slough and that in a sense was a piece of social history if you like, whereas now its coming into the political years where its more familiar territory.”

By now the boy who stacked shelves in Tesco had risen through the ranks at the Post Office, won a vital campaign against privatisation before embarking on a meteoric political rise.

I ask him what his younger self would have said if they’d told him one day he’d end up a government minister.

“Don’t be daft. It was extraordinary. I had no ambition to be an MP. I had ambition to be the leader of the union which I did and once I got there I had a very successful campaign against John Major’s attempt to privatise the Post Office and we beat that and I led the campaign so it gave me a kind of profile and the next thing I’m being asked if I want to be an MP, to which I said no, but in the end my predecessor had left to join the peerage halfway through the 1997 general election and I was asked if I wanted to parachute in and I made that choice.

“It would have been unimaginable as a postman and before that stacking shelves and dreaming of being a rock star. But with most people’s lives its a series of events that take you closer and closer to your eventual destiny and, once I became an MP, we were the party in government and quite quickly I was promoted to the junior ranks of ministerial life.”

In the book Alan delivers a refreshing combination of the professional and the personal, so we get to see the man behind the policies and who helped make him the way he is.

“People are always interested in what happened to my sister Linda who is very much the hero of the first book,” says Alan. “She actually moved to Watford and I could have ended up living there. My father left when I was eight and my mother died when I was 13 so she was virtually bringing me up aged 15-16 she managed to get a council flat for us in a flat in Battersea. Then she got married and moved to a semi detached house St James Road, in Watford. She asked me to move in but I said I’m not moving to the north.”

As well as being candid, the book is deeply moving, especially in the chapter when he describes how his daughter Natalie died in childbirth.

“I had to force my hand across the page, but once you start to write a memoir of your life you can’t miss something out like that and although I’d never made it public at the time because it was nobody else’s business but ours, once you start to reveal stuff you can’t hide away from that. I also wanted to make sure people knew Natalie had lived just as much in the first book my mother died young and, in a sense, I was trying to be her biographer and make her live again on the page and with Natalie it was similar – it’s almost like denying she ever lived if you leave that out.”

Alan talks with equal passion about the trawler men who worked in temperatures of -40 and suffered losses of 8,000 men in 150 years. Having won compensation for them he has gone on to petition for their pension rights.

Alan says this is one of the highlights from his years in office along with getting people off incapacity benefit, pension credit, bringing down waiting times down for operations and raising the leaving age for education.

It is a wonder to think so much could be done, especially in a day job that Haifa few quirks and eccentricities.

“This is about the Houses of Parliament as a workplace and so I’m describing the government car service drivers and my private office just as much as the MPs and ministers I worked with.

In some departments Yes Minister seemed more like a documentary than a comedy programme.

“Generally the quirkiness was more around Parliament, if you wanted to raise a point of order in the house you had to stick a stupid top hat on your head.

“At the department of Trade and Industry every single civil servant stood up when you walked into a room which I found very uncomfortable and they never called you by anything other than minister, which I understand. I said why don’t you call me Alan but it was very important for them to keep that distance, they’re the permanent civil servants and you’re the temporary minister who’s passing through.”

Chorleywood Memorial Hall, Sunday October 16, 6pm. Chilternbookshops.co.uk.