Alex Rider TV series is darker than 2006's Stormbreaker movie, says Anthony Horowitz

Though a broadcaster for the new eight-part series is yet to be confirmed, we do know it will begin with a version of the second Alex Rider novel, Point Blanc.

"I've seen the first four episodes and, from the starting point of being quite nervous about what it was going to look like, I have to say I'm absolutely thrilled," author Horowitz told RadioTimes.com.

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"Otto Farrant is the perfect Alex, he is really wonderful. There's another young actor called Brenock O'Connor who plays Tom, his best friend, and the two of them are just wonderful on the screen together – and of course we're very lucky to have Stephen Dillane and Vicky McClure playing Alan Blunt and Mrs Jones, so it's a terrific, very international cast."

Horowitz described the Alex Rider show as "quite an adult piece", saying, "I think people are going to be surprised how adult it is. I don't like the phrase 'family drama' because I'm not sure it exists anymore – do families really sit down at 7pm and watch television together? But in the broader sense of, can parents enjoy this programme as much as children? I very much hope so.

"When I conceived of Alex Rider, I always described them as 'adult books for kids' – I think that's part of their success. They didn't feel when like children's books when I wrote them."

Horowitz has written 12 books featuring youthful, somewhat reluctant MI6 agent Rider, with a 13th expected to be released next year. The award-winning novelist wrote the screenplay for the Stormbreaker movie, while Guy Burt (The Bletchley Circle, Riviera) has stepped in for the television show.

"Guy Burt came in and has done an extremely good job with the scripts, I couldn't be happier," Horowitz said. "If I had one criticism of the film, it was that it played too young. I wish it had a little bit more edge to it, a little bit more violence.

"I say this to you now... it's not good practice for anybody who worked on a film to break ranks. Decisions are made at the time and you go along with the flow. Making a film is like being on a cruise liner – getting it to stop or tune round takes all hands to the deck. So I'm not criticising the film.

"But when I saw it, I wished there had been just a little bit more edge to it, a little bit more darkness, a little bit more danger. I think that's what the TV show has, which is why I'm so excited. I mean, I love the film too, but the TV show is textually very different."

The new Alex Rider series started filming in April, but an air date and broadcaster for the show is yet to be announced.

Anthony Horowitz's new novel The Sentence is Death is out now.