The author of the best-selling Jack Reacher novels is handing over the writing duties to his younger brother.
Lee Child, 65, reportedly considered killing off the 6ft 5ins vigilante hero, who is played by actor Tom Cruise in film adaptations.
But the writer said: "I love my readers and know they want many, many more Reacher stories in the future."
His brother Andrew Grant, 51, who will write under the pen name Andrew Child, is already an established author.
Child, whose real name is James Grant, said he felt he was "ageing out" of being able to produce more of the books.
He said: "So I have decided to pass the baton to someone who can."
He described his younger sibling as the "best tough-guy writer I have read in years."
"We share the same DNA, the same background, the same upbringing," he said, adding: "He's me, fifteen years ago, full of energy and ideas."
The Coventry-born author said they would work on the next few novels together "and then he'll strike out on his own".
Child started writing after being fired from his job as a presentation director at Granada Television in 1995.
His first Reacher novel, Killing Floor, was published in 1997.
He has since sold more than 100 million books and Amazon has announced it is adapting the series for TV.
The novels, which are set in the United States, have been translated into 40 languages and adapted into two movies starring Cruise.
The protagonist of the book series is a former major in the US Army military police who roams the US investigating suspicious and dangerous situations.
Grant said he had been "blown away" by his elder brother's first Reacher novel.
He said: "The more time I spent with him in each new adventure, the more I craved the next. So I know what it's like to wait for the new Reacher novel."
He added: "I understand what Reacher fans want - because I am one. And I'll do my best to deliver for them.
"I'll have to. Because my big brother will be watching."
The Sentinel, the 25th Jack Reacher novel, is due to be published on 29 October 2020.