Poirot star David Suchet has revealed that Agatha Christie's family warned him not to play the Belgian detective as a joke when he was first approached about the role.
Suchet, 67, who signed up to play the much-loved character 25 years ago, has filmed his final scenes as the mustachioed sleuth and Curtain: Poirot's Last Case will be broadcast on ITV later this year.
The actor insisted he would be happy to see someone else take up the mantle of Hercule Poirot following his retirement from the role.
Suchet told the Radio Times that crime writer Christie's family ordered him not to portray Poirot as a figure of fun.
He said: "In the books, as opposed to some of the films that have been made, he is not a comic character.
"I was told by Agatha Christie's daughter and her husband over lunch, 'If you're going to make him a joke, then you are not going to play him; people can smile with him, but never laugh at him'.
"That was a very strict order I was given, and when I started reading the novels, I realised exactly what they were saying, because he's not just a figure of fun. He could never be with that brain."
Suchet said that "I now own him (Poirot) in a way" and that the detective was "now my character".
But he said that he would not mind if ITV or another broadcaster brought Poirot back, adding: "I think there would have to be a generational gap, but yes. I've been in so many classical plays that have been made famous by other actors. In time, no one is totally indispensable. There will be another take; maybe there will be a young Poirot?"
He said of getting into character: "As soon as the moustache goes on, I speak as him ... the voice of Poirot is kicked in by the moustache, and once the voice is there, every single thing about him slots into place."
Suchet said of the danger of being typecast: "Poirot could have been the end of my career. It's so easy for that to happen, but it didn't."