LONDON •A sleepy English village. An unexpected death. Then another. A foreign detective with pedantic habits and a host of potential suspects with secrets to hide.

Sound familiar? No, this murder mystery is not by Agatha Christie, but by Anthony Horowitz, whose Magpie Murders was published by Harper in the United States last week. It is the first original murder mystery novel from Horowitz, best known for his Alex Rider spy series for teenagers.

In Magpie Murders, Horowitz, 62, makes gleeful use of the Christie format by creating a 1950s mystery within another mystery, set in contemporary London.

"I've always loved the genre and I've written dozens of murder mysteries for TV shows, but have resisted writing one as a book until now," he said in his London home.

The living room is filled with contemporary art and books. He proudly pointed out a secret room - a small shelf-lined space hidden behind a bookshelf, displaying objects related to magic and tricks.

"I'm not good at magic, but I love it and am always reading about it," he said. "A lot of what constitutes a whodunit, just like a magic trick, is misdirection. It's not what you have seen, but what you think you have seen."

Although he has written two Sherlock Holmes novels, sanctioned by the Conan Doyle estate (Moriarty, 2014, and The House Of Silk, 2011), he said he had hesitated to write an adult mystery in his own voice.

"I felt I needed to do something more than just invent a detective... with a sidekick, and then a murder and a solution," he said. "Writing for me has always been about pushing the envelope and I began to think of ways I could use murder mysteries to do other things.

"I don't think anyone has done a story within a story, with two interlinked crimes, like this, so I'm pleased."

The plot, he said, was inspired by the fact that Arthur Conan Doyle, who invented Sherlock Holmes, "the greatest detective ever created", came to hate his character.

"I had similar feelings about Alex Rider. He is handsome and successful at 15 and I'm an ageing writer in an attic in London," said Horowitz, whose 2000 publication of his first Rider spy novel, Stormbreaker, gave him the breakthrough.

The series has sold about 19 million copies worldwide and an 11th novel, Never Say Die, will be published this year.

Horowitz said Magpie Murders took about five months to plan.

"It was a very difficult book to write because the second part has to connect with the first," he said. "Every character has two identities in a way, but it also had to be easy to read and understand. The most important thing for me was that you couldn't guess the ending, but that every clue is on the page."

He placed the novel in the 1950s because he likes murder mysteries that are without surveillance cameras and DNA. "I want sprinklings of clues and red herrings," he said. "And having no mobile phones is wonderfully helpful. It slows the pace down and you have more time for atmosphere and character."

He writes every day, using a fountain pen for his first drafts ("I love the physicality, the scratch of the nib, the crumpled balls of paper").

He has already finished his next adult-murder mystery, in which he has written himself into the plot as the sidekick. "Of course, I'm the one who is constantly fooled," he said.

He added: "A book does magic without saying: Pick a card. A whodunit is, at its best, a huge magic trick that says: I'm going to tell you a story."

NYTIMES

•Magpie Murders by Anthony Horowitz ($30.06) is available at Books Kinokuniya.