No mystery: it’s curtains for Hercule Poirot as David Suchet says goodbye after 25 years

For 25 years, actor David Suchet has played Hercule Poirot, inhabiting every pore of the Belgian detective once described by his creator Agatha Christie as “a detestable, bombastic, tiresome, ego-centric little creep”.

In that time hundreds of millions of viewers have disagreed, enjoying Suchet’s portrayal in more than 70 television films, shown so far in 100 countries and dubbed into 80 languages.

When he was offered the part, in 1987, Suchet, who was already a well-regarded character actor, had to admit that he had never read Christie's work, which had begun in 1920 with the publication in the United States of The Mysterious Affair at Styles.

But he had seen Albert Finney's portrayal in Death on the Nile. He began to read Christie's books. He soon took the view that the character she had created had never been brought to life.

“The one thing I decided was to be true to Agatha Christie. I wanted to make it right for her,” Suchet told Poirot fans this week in London, each of them able to finish the lines of the best-known scenes in the ITV series.

The close relationship between fans and the series is nothing new. In the mid 1990s Suchet, wearing full costume – the pince-nez, well-cut suit and cane topped with a silver swan – left the film set one summer evening in Hastings, on the south coast of England.

“I was very, very tired at the end of the day. I just needed to get away. We were out on location on a little road. I leaned on my cane and went, ‘Phew’,” he says, gesturing to show his exhaustion. “Then there was a little old lady with her shopping trolley, and she looked at me. I looked at her, and she looked at me again. She says, ‘Well, hello, Mr Poirot.’ What do I do? What do I do? I am resting off the set, but dressed as Poirot.

"I suddenly realise that I have got the moustache and the hat. I can't reply, 'Well, hello, love, are you doing all righ'?" Suchet says, slipping into a south London twang. "I just can't do it. So I said, 'Hello, Madame', moving back into Poirot's character. She says, 'What are you doing here? There hasn't been a murder or anything?' I said, 'No, no, no: no murder in Hastings. I am here en vacances.' She says, 'Who?' I said, 'I'm here on holiday.' She says, 'I'm so pleased.'

"She walks on, but then she suddenly turns around and says, 'Can I say one thing, Mr Poirot?' 'Oui, madame?' 'Thank you so much for choosing Hastings,' " he says, his pleasure at the memory undimmed.

Two of the four episodes in the last series have been shown. The final one, Curtain, will be broadcast on November 13th – though Dead Man's Folly, which has just been shown, was the last to be filmed.

Curtain, which was filmed on a sealed set, records the detective's death. Neither Suchet nor those associated with Poirot over the decades could face the prospect of filming his death scenes last, so they were done earlier.

“Yes, I will miss him, though I’ll be able to see him quite a lot on ITV3. He has been like a best friend. I’ll miss not inhabiting him. But I will never allow myself to do get too mournful about it. No, I celebrate it.”

Christie's daughter
Today, few can imagine another actor in the role. That was not always the case. Christie's daughter Rosalind Hicks and her husband, Anthony, who became great friends with Suchet, had to be convinced over lunch.

"I thought I was going to be taken out for a lovely celebratory meal, to say, 'Good luck, everything is going to be fine.' I ended up being the grill," he says. "I remember very vividly them saying, 'Look here, we do not want anyone to laugh at Poirot. They will smile with him.' I said, 'Okay.' I got the message. In the earlier series when there is a lighter touch, as there is in the earlier short stories, they are amusant without being comic. I hope and I pray I never crossed that line."

Ten years after she had created him Christie was sick of her best-known character, but his popularity saved him. During the second World War, in case she was killed, she wrote the final book, with Poirot returning to Styles one more time.

But it was not published until 1975, a year before the author died. "Did she know when she wrote The Mysterious Affair at Styles that he was going to become such a hit and last another 50 years? No, of course not."

Occasionally, Poirot becomes judge and jury, letting murderers go free in Murder on the Orient Express – look away now, if you have not read it – because the man killed "deserrrrvvvved to die", Suchet emphasises.

The final scene in his re-creation of that novel, one that shows Suchet walking away from the train with a backdrop of lightly falling snow, is one of the best known, showing the detective in tears, displaying his internal struggle to the world.

“That is the dilemma. You cannot believe that that eccentric little man, with that deep core inside him, as a very committed Catholic, would just go, ‘Okay’. No, that costs. It cannot not cost when you really get him.”

Christie “created this outsider. I have always enjoyed playing outsiders, I really do. [He’s] very compassionate and charming with ‘below stairs’, if you know what I mean. He is a gentle man, as well as being, as we know, a gentleman.”

Suchet’s preparations for the role were intense: he drew up 96 one-liners that he still carries around – how many lumps Poirot takes in his tea or coffee, for example – and his many mannerisms.

Twenty-five years on, Suchet certainly knows Poirot. “He does these silly little things: fussy, obsessive compulsive. I think to myself, Stop it, let go – and then I realise that I am the one doing it.”