The Silver Citadel), and was released on 2 April 2007. The fourth book Necropolis (based on Day of the Dragon) was released in October 2008. The fifth and final book, the only one not based on an earlier Pentagram novel, was released in October 2012 and is called Oblivion. Horowitz describes this series as "Alex Rider with devils and witches". In October 2008, Anthony Horowitz's play Mindgame opened Off Broadway at the SoHo Playhouse in New York City. Mindgame starred Keith Carradine, Lee Godart, and Kathleen McNenny. The production was the New York stage directorial debut for Ken Russell. In March 2009 he was a guest on Private Passions, the biographical music discussion programme on BBC Radio 3. Continued success (2011–present) On 19 January 2011, the estate of Arthur Conan Doyle announced that Horowitz was to be the writer of a new Sherlock Holmes novel, the first such effort to receive an official endorsement from them and to be entitled The House of Silk. It was both published in November 2011 and broadcast on BBC Radio 4. A follow-up novel, Moriarty, was published in 2014. In October 2014, the Ian Fleming estate commissioned Horowitz to write a James Bond novel, Trigger Mortis, which was released in 2015. It was followed by a second novel, Forever and A Day, which came out on 31 May 2018. A third novel entitled With a Mind to Kill was announced in May 2021 and will be released in May 2022. Horowitz is the only author in recent years to have been invited by Ian Fleming Publications to write successive, official James Bond novels. In 2016, Horowitz's adult novel Magpie Murders was published. Having previously spoken about the book in 2005, it was initially described as being about "a whodunit writer who is murdered while he's writing his latest whodunit". Horowitz finally expected to finish it in late 2015, and it was finally published in October 2016. A follow-up novel, Moonflower Murders, was released in 2020. A third and final novel in the series is expected to be released as well, with Horowitz expressing hope that he'll start writing it sometime in 2023. In 2017, Horowitz began a new series of detective novels which includes himself as a novelist enlisted by an out-of-work detective called Hawthorne to write books about the way Hawthorne solves crimes. The fictional Horowitz accompanies Hawthorne as he investigates murders committed