Slow Horses creator reveals shock ending for Jackson Lamb - 'How, why, when and where'

Slow Horses star Gary Oldman says he wants to play lead character Jackson Lamb for "the long run" - so he'll be spooked to hear writer Mick Herron is planning to kill him off. The Oscar-winning actor, 67, has made it clear that he will happily play the flatulent, dishevelled spymaster in the fictional Slough House for as long as they want him.

But Mr Herron, the programming chair for this year's Theakston Old Peculier Crime Writing Festival, supported by the Daily Express, revealed he recently made a big decision about Lamb's future. During a panel event with Slow Horses screenwriter Will Smith on Saturday, Mr Herron admitted: "This is just between you and me, but I do know how, why, when and where Lamb dies."

His comment drew gasps from the audience, prompting Mr Smith - previously a writer for BBC sitcom, The Thick of It - to say: "You have never told me that before."

Mr Herron replied: "I have never told anybody. It's quite a recent development... I have realised certain things about the series, how it will go." Mr Herron, 62, had been responding to a question from Mr Smith, who asked: "Do you have an end point for Lamb, because it feels like he could go on forever?"

After Mr Herron's bombshell response, the screenwriter, 54, probed: "But you don't have a date?" To which the author cryptically replied: "Do I not?" This clearly shocked Mr Smith, who added: "I have my private list of characters I think you won't touch and you have just blown it!"

Actress Saskia Reeves, 63, who plays Lamb's trusted office manager Catherine Standish in the Apple TV show, also made a surprise - appearance at the event at the Old Swan Hotel in Harrogate, North Yorkshire. Other special guests over the weekend included US author Attica Locke, Lee and Andrew Child, Kate Atkinson, Val McDermid and broadcaster Steph McGovern.

Mr Herron's latest Slow Horses book, Clown Town, will be published in September.

And with the fifth series of Slow Horses set to premiere in September, and seasons six and seven already commissioned, fans of the show need not panic that the end is nigh for the much-loved main character. But all will be revealed in time...