The final curtain is about to fall on TV’s iconic Belgian detective Hercule Poirot as he solves his last ever murder case.

And for award-winning actor David Suchet it is the end of an era, as he lays down his cane after 25 years in the role.

“It’s hard to believe I’ve done 70 of Agatha Christie’s stories,” says David, 67, who admits that saying goodbye to the much-loved character was difficult.

“The last day of shooting was very, very hard,” he says. “There was a party afterwards and then I just left the next day. That was it! I really hope I will be able to keep my cane – and the moustache won’t be going back either!”

In Curtain: Poirot’s Last Case, the elderly and wheelchair-bound detective calls on his old friend Captain Hastings (Hugh Fraser) for help as they return to the scene of their first case, the rambling Styles Court, to prevent a murder.

Hastings is now a widower and Poirot has a life-threatening heart condition, but he must summon the last of his strength to find out who the killer is before he dies.

The adaptation also stars Anne Reid, Philip Glenister, Helen Baxendale and Matthew McNulty.

“You see Poirot as a wizened, tiny, thin old man,” says David. “I had to lose two and a half stone for that. It was tough because dieting is the hardest thing in the world.”

David explains that the final scene he shot as Poirot was actually used in an earlier episode as they aren’t filmed in the order of transmission.

“I think I had one line,” he says. “I had to say to Madam Oliver, ‘Is he the owner of the house?’ and she replied ‘Yes’. And that was my last line as Poirot. I mean, what an anti-climax after 25 years!”

But David reveals viewers will be saddened to see the death of their favourite detective. “When we filmed Curtain, I shot his death over two days,” he says. “But then I had to go back and do a scene with him writing a letter, which was good because I didn’t leave him dead. People will watch him die, but then they will, of course, see re-runs.”

And the actor, who has a career in TV and theatre spanning more than 40 years, admits Poirot will always
stay with him.

“It’s a marriage, isn’t it?” he says. “It’s 25 years of friendship that I’ve developed with this man. I know him as well as I know anybody – maybe better. I will remember him with great fondness and gratitude.”

* Don’t miss Being Poirot (Wednesday, ITV 10.35pm) in which David investigates the enduring appeal of the detective and reveals what it has been like to play the world-famous sleuth.

Agatha Christie's Poirot: Wednesday, ITV, 8pm