success of the Harry Potter series. In the same year, Horowitz publishing a collection of several short horror stories aimed for children and young adults, entitled Horowitz Horror (1999). This was an opportunity for Horowitz to further explore a darker side of his writing. Sometime before the new millennium, Horowitz attempted to reach out to an adult audience with a novel called Poisoned Pen. The novel is based around Martin Holland, who is a childhood friend of a 21st century incarnation of William Shakespeare. In the novel, William Shakespeare is reimagined as a Hollywood screenwriter who is murdered in a set of circumstances that Martin Holland finds rather odd, despite attempts from a Los Angeles detective to dissuade him. The novel follows Martin's attempts to solve the ever-growing mystery through a series of rather unusual circumstances and a number of people who seem rather glad that Shakespeare was murdered. The novel has never been published in the UK or even in English, but copies in Spanish and Dutch have been released (retitled as El asesinato de Shakespeare and William S. respectively). As of June 2021, despite Horowitz's recent successes in adult literature, there are no plans to get the novel republished. Mainstream children's fiction success (2000–2010) Horowitz began his most famous and successful series in the new millennium with the Alex Rider novels. These books are about a 14-year-old boy becoming a spy, a member of the British Secret Service branch MI6. As of 2021, there are eleven books where Alex Rider is the protagonist, and another connected to the Alex Rider series: Stormbreaker (2000), Point Blanc (2001), Skeleton Key (2002), Eagle Strike (2003), Scorpia (2004) Ark Angel (2005), Snakehead (2007), Crocodile Tears (2009), Scorpia Rising (2011), plus Russian Roulette (2013). Horowitz had stated that Scorpia Rising was to be the last book in the Alex Rider series prior to writing Russian Roulette about the life of Yassen Gregorovich, but he has returned to the series with Never Say Die (2017) and Nightshade (2020). In January 2022, he announced that he will begin writing a new Alex Rider novel that is due to be published sometime in 2023. In 2003, Horowitz also wrote three novellas featuring the Diamond Brothers: The Blurred Man, The French Confection and I Know What You Did Last Wednesday, which were republished together as Three of Diamonds in 2004. The author information page in early editions