There is a light that never goes out - and its name is Jimmy Perry

The concert-party sitcom It Ain’t Half Hot Mum (1974–81) drew audiences of 15 million and its successor, the holiday-camp-set Hi-de-Hi! (1980–88), up to 17 million. Perry and Croft’s final collaboration, the comedy drama You Rang, M’Lord? (1988–93), was less popular but has since been critically reappraised.

But it was about Dad’s Army that I chiefly wanted to talk to Jimmy in 2014. The show hit highs of 18 million viewers on its original nine-year, 80-episode run, ending in 1977. But the BBC2 Saturday-night re-runs were proving astoundingly popular (and still are), their two million or so viewers prompting schedulers to call the 40-year-old programme “ratings crack”.

It helped that Jimmy was already a fan of Radio Times, incidentally the same age as himself: “I think the Radio Times is a bloody good magazine!” he said.

Jimmy agreed to give me an hour of his time at his flat in Hammersmith but three hours later, I was still being entertained. It was clear that the creative impulse still burned brightly in this twinkly nonagenarian, and our wide-ranging conversation took in showbiz, music, censorship, fathers and sons, Mrs Brown’s Boys and being truthful in comedy.

Fond of bespoke tailoring and partial to the odd frangipane, Jimmy proved to be a master raconteur whose love of show business seemed to run in his blood.

He seemed genuinely bowled over by Dad’s Army’s continuing success: “Isn’t it amazing? Let me tell you, I’m overwhelmed.

“It was so easy to work on,” added Jimmy, who explained that he and David Croft tailored their scripts to the actors’ personalities. “What we did, after about ten episodes, or even before that, people slowly drifted into the part as themselves - and it worked.”

Perry’s idea for Dad’s Army came from his teenage experiences in the Watford Home Guard. In 1967 he gave a script to Croft, a TV producer, who loved it. Basing comedy on real life was vital to Jimmy Perry, who was once told by George Bernard Shaw, no less, “You must have reality, otherwise it’s rubbish.”

People assume that the Perry and Croft partnership was a marriage made in heaven but Jimmy did admit to me, “I must be honest, sometimes he got up on my nerves. He was different to me, entirely different. But never did we have a row. We had a rule, that if I wanted something he didn’t like, I wouldn’t push it. And if he wanted something that I didn’t like, he didn’t push it. We had no problems. He was an amazing man, David.”

Jimmy told me that, just occasionally, actors proved temperamental. “We kept discipline. We had to. That’s how we controlled it, but without any nastiness. You don’t need to be bitchy. You can’t say to them, ‘What makes you think you can write?’ But all actors think they can write and want to change things. Take their pencils away from them! But no, David and I never lost our tempers or bullied actors.”

Dad’s Army fans are many, and include celebrities like Miranda Hart, Jack Dee and Richard Osman. For Jimmy, too, Dad’s Army never got old. “I know every line. I sit and watch it with Mary [his partner Mary Husband, a costume designer].” And his fave episode? Branded, in which Godfrey [Arnold Ridley, who fought and was wounded at the Somme] is revealed to have been a conscientious objector in the First World War. Jimmy recalled Mainwaring’s incomprehension: “‘Not wanting to fight, it’s just not normal.’ Those aren’t my lines. I’ve heard them. Dear Arnold, you know he had this terrible bayonet wound right up his arm.”

Despite Dad’s Army’s huge success, his own front-runner from the Perry/Croft hit factory was their follow-up series. “When I came out of the war I was a sergeant in the artillery in the Far East in Burma. I was 19, the war had finished, and I had an idea from that, which I pinched for It Ain’t Half Hot Mum. That was my favourite. I love it. ”

Clearly it rankled with Jimmy that the BBC hadn’t repeated the show, in which an English actor played an Indian character, Rangi Ram. But he wouldn’t be drawn on that subject: “Be careful now. You might as well be in Stalin’s Russia. You don’t want to upset anyone!”

Of his contemporaries, Jimmy especially admired the work of Galton and Simpson, and Steptoe and Son in particular. “That marvellous relationship. That’s what I love to write about: people who are chained together… comedy is just next to tragedy and sadness.”

He was less of a fan of what he called “Terry and June-style sitcoms. ‘Yoo-hoo darling, I’m home’. I’m not knocking it. If that’s what people like, and that’s what they want, give it to them.”

As for today’s sitcoms, Jimmy said, “Let me tell you my favourites. It puzzles me, but I love Mrs Brown’s Boys. Because it’s so showbizzy, I suppose. They break every rule in the book. And that one with two old queens bickering, Vicious. I think it’s great. And Count Arthur Strong - I love it!”

Jimmy believed he’d had a lot of luck in his career: “It’s a great privilege to do what you want to do. I’ve followed what I wanted to do.”

He spoke fondly of his father, an antiques dealer whose love of the theatre proved infectious. And he was keen to hear about my own family and life story. I told him that my father had introduced me to Dad’s Army and we then enjoyed watching the show together. While any random mention of the programme tends to draw the catchphrase “Don’t tell him, Pike”, it’s another moment from the show that made my dad cry with laughter, and one that I’ll therefore never forget...

In the episode Battle of the Giants!, the platoon are on a training exercise and have to use their initiative to pop all the balloons that are released by the Verger. With time running out, Captain Mainwaring unholsters his revolver and shoots down one rapidly disappearing balloon from the sky. “Good heavens!” exclaims Wilson, to which Mainwaring replies, “What do you mean, ‘Good heavens’?” One double take later, the dumbfounded captain says, “Good heavens!”

So for my father and me, it was never “Don’t tell him, Pike”. Always “Good heavens!”

Jimmy seemed touched at hearing of the bond, and by the fact that I had introduced the show to my children.

It was a privilege to have known Jimmy, if only for a short time, but at a time when he was still enjoying the fruits of his success, and meeting a new generation of fans.

His health suffered in the last year or so, and it took an old soldier’s effort to make the red-carpet world premiere of the Dad’s Army film last January. But I was thrilled to see Jimmy witness his creation writ large, with a big budget and a hugely impressive cast. And also to see the story of Dad’s Army’s origins re-enacted in the well-received BBC2 drama We’re Doomed!

One of Dad’s Army’s legion of catchphrases was “Put that light out.” But thanks to his imperishable sitcom there is a light that never goes out - and its name is Jimmy Perry.