Originally published in 2014.

Some days you wonder why you bother - ‘celebs’ who have been famous for 14 minutes, ‘personalities’ who have had theirs surgically removed, and PRs who appear to have confused themselves with God.

So what a treat, then, to find myself on the office blower to someone who only has to say the word ‘Hello’ for me to be transported instantly to the cramped office of a church hall in Walmington-On-Sea and who, while he may have turned tetchy into an art-form, is sweet and helpful and delightfully mannerly.

I’m talking to him because he’s coming to Christchurch’s Regent Centre tomorrow with a one-man performance, talking about his life in the business of show, and screening off-screen footage of downtime from the tour-de-comic force that was Dad’s Army.

Nearly in his ninth decade, shouldn’t he be retired by now?

“I think actors don’t retire, I think they simply fade away and Dad’s Army is one of the proofs of that,” he says.

“John Laurie (Frazer) and Arnold Ridley (Godfrey) more or less started a new career in their late 70s and when they finished the series Arnold Ridley was the same age as I am now and still working.”

It’s nearly five decades since David Croft and Jimmy Perry asked him to take on the small part of the Reverend Timothy Farthing in their new sitcom about life in the Home Guard.

“It was very tiny, a couple of lines really, and I probably said ‘Oh really, is it worth doing?’” he says, sounding delightfully tetchy for a second.

“But I said yes because I had known Jimmy Perry for ages, firstly at the repertory theatre at Watford and then from 1959-1961 in The Army Game.”

That tiny part grew and grew to become the one for which he became world-famous: Dad’s Army played all over the world and is a solid feature of the TV schedules today.

“I always say it was the happiest time of my life. There was such a lovely group of people to work with, not only on the TV but the radio spin-off, the feature film and a musical stage show,” he remembers. Then there was the touring stage show in 1976 when they went to ‘lovely places’ and got to know each other very well.

He thinks part of the success was down to it being like the old-fashioned ‘actor’s company’. “Everyone knew what they were doing and slotted in.”

During this time he acquired a cine camera and started making back and off-stage films. With the help of the Dad’s Army Appreciation Society, he put a commentary to it and it is this film visitors to his show will be able to view. “There’s some nice footage of us at Longleat and places like that.”

There are a million things I could ask him about Dad’s Army but I wondered if any of the characters were really like themselves in private life?

“As the series progressed they began to write the idiosyncrasies of the actors into the characters,” he explains.

“I suppose the real exception to the character you saw was that of Ian Lavender who is very far from being a stupid boy - he was one of the most intelligent of the lot of us.”

For Frank, however, life did begin to imitate art when he found himself becoming a member of the General Synod of the Church of England.

“I’m a churchgoer and a friend of mine suggested I stood as a lay member in1985, eight years after we’d finished the series.”

He stood as a candidate for London and served three terms which meant he also got to know the former Archbishops of Canterbury George Carey and Rowan Williams.

“I can remember one occasion when I was voting and went through the laity door and one of the tellers stopped me and asked if I was going through the right one!”

But the teller can be forgiven because Frank has specialised in members of the clergy.

He was a vicar in Gas and Gaiters and Hi-de-Hi and Hallelujah with Thora Hird, then an Archdeacon and finally, a bishop in You Rang M’Lord, for Perry and Croft again. “I’m sure I could play Archbishop of Canterbury now, if they asked,” he jokes.

During his time in the show he learned that it was the Queen Mother’s favourite programme, from no less and authority than Prince Charles.

“He told me ‘that was my dear grandmother’s favourite programme’,” he says.

“I was told she would go home after a busy day, have a drink and ask her butler to put on a Dad’s Army video for her.”

Her favourite episode was his, also, featuring the Royal Train. “I think she liked it was because it specifically mentioned her husband King George.”

Frank is so kind and polite that I could have spent all day chatting. However, he has a show to do and it is there you can ask him the questions you want answered as he always includes an audience Q and A.

Given his oeuvre and the fact that he’s worked with Morecambe and Wise, Harry Worth and the immense Tommy Cooper there is probably enough to keep him going for a week.

But when you’re a member of a show that’s lasted longer than 40 years, maybe you get used to it