“Did you hear that? You called me Nigel!” says the actor Graham Seed.

I had indeed — if you can collapse in confusion on the telephone, that is what I did. Seed was, of course, Nigel Pargetter on The Archers from 1983 until famously falling off a roof in January 2011.

Graham doesn’t let go: “You do know I’ve got a one-man show called Don’t Call Me Nigel, don’t you?” “Yes, Graham,” I splutter and try to change direction and get a quote about the editor of the radio series who decided to kill the character off.

“Vanessa Whitburn’s a tough cookie, isn’t she?” “You might say that, but I couldn’t possibly comment!” he comes back smoothly.

Which of course, is a perfect link: Seed classically quotes from the oily Francis Urquart in the 1990 political thriller House Of Cards just as he comes to the Playhouse next week as Jim Hacker in Yes, Prime Minister — the hit stage comedy crafted by Antony Jay and Jonathan Lynn from their wonderful 1986-8 TV series. It’s a new story, but he and Michael Simkins — who plays Sir Humphrey — have that mountain to climb: erasing that memory inbred in us all of Paul Eddington and Nigel Hawthorne in the roles. I asked him about facing up to the Eddington comfort zone: “Eddington was sublime, charming and brilliant… and vacant and vulnerable. There is no way I can pretend to be him, and I wouldn’t, because I’m Graham Seed! This play is more of a farce than Yes, Prime Minister was on television, but I hope the audience may feel the warmth through the writing. Hacker’s not the brightest thing on the planet sometimes, but the play’s a fascinating exploration of the art of one-upmanship between the politicians and the civil servants”.

The plot needs not detain us long: Hacker as Prime Minister of a coalition government is governing a country facing economic disaster.

But there is a possible way out: doing a highly dubious deal with the foreign minister of that well-known country, Kumranistan. Private secretary Bernard is there, as is the equally essential special policy advisor. And the director-general of the BBC.

Ah, the BBC. When Graham —sorry, Nigel — died 14 months ago, the actor, in interviews he gave after the event, was clearly shocked and had no jobs immediately coming his way. “Nigel Pargetter had been a huge star of The Archers in the ’80s and ’90s, but the writers hadn’t written for him very well in the previous seven or eight years and I was beginning to think: ‘Why aren’t I [Nigel] having good stories?’ “When I was told, I can confirm she [Whitburn] said it was a ‘good story’: for the publicity machine. She wanted a birth and a death in the 60th anniversary episode and there wouldn’t be much point killing off a character who wasn’t much loved”.

Seed pauses and you can feel it still hurts. I suggest that, by definition, the results weren’t all bad: if Nigel hadn’t been written out, the Graham Seed name-recognition factor wouldn’t have been as high and he certainly wouldn’t be leading this major tour and have people like me having chats like this: “Absolutely. I made a huge decision I was not ‘done’. What you hinted at is right: it ain’t done me any harm. I’m a working actor, thank God, trained at RADA and let’s hope there’s some life left in me yet: I was in a play called Accolade, which sort of relaunched me and told me that I wasn’t just a radio voice, and I toured with Nigel Havers last year in a new play. The theatre has rescued me but…” and here’s the rub, “I miss radio, I love radio drama and I hope I’ll go back to radio”.

Note to Graham: Vanessa Whitburn apparently goes on ‘long-service leave’ from Radio 4 in July.

Yes, Prime Minister is at the Playhouse, March 5-10.