Question: How many series does have the adventure novels who's first novel is The Maze of Bones?
Context: The Maze of Bones is the first novel of The 39 Clues series, written by Rick Riordan and published September 9, 2008 by Scholastic.  It stars Amy and Dan Cahill, two orphans who discover, upon their grandmother Grace's death, that they are part of the powerful Cahill family, whose members constantly fight each other for Clues, which are ingredients to a mysterious serum.  The novel has received generally positive reviews. Athena Force is a series of adventure novels about graduates of the Athena Academy, an elite school for girls with special talents, as they combat kidnappers, terrorists, and the forces of evil.  Published under the Silhouette Bombshell imprint, the first continuity of novels dealt with a group of friends who all graduated from the Athena Academy—each had her special gift or skill, and each had her own adventure.  One of the elements that related them was the mysterious death of one of their classmates.  The second continuity told a different, less-connected story using the same background but new characters.  For the third (aka "Arachne") continuity, the series moved to Silhouette Special Releases after the Bombshell imprint was shut down by Harlequin Enterprises in January 2007. Giles Kristian (born 1975) is a bestselling novelist, known for his action adventure novels in the historical fiction genre.  He is best known for his "Raven" series, about a young man’s coming of age amongst a band of Viking warriors.  His first novel, the bestselling "Raven: Blood Eye," was published to great acclaim (including an accolade from Bernard Cornwell).  Two further novels complete the "Raven" Saga, "Sons of Thunder" and "Odin's Wolves", and to date the books have been published in eight languages.  He has written two books set during the English Civil War 'The Bleeding Land' and 'Brothers Fury' published by Transworld Publishers.  In 2015 he co wrote 'Golden Lion' with Wilbur Smith, part of Smith's best selling Courtney series.  He is currently writing the second book in the Raven prequel series, following the exploits of Sigurd 'The Lucky', the first being the 2014 release "God of Vengeance". Mary Mackey is an American novelist, poet, and academic.  She is the author of seven collections of poetry and fourteen novels, including the "New York Times" best-seller "A Grand Passion" and "The Village of Bones", "The Year The Horses Came", "The Horses At The Gate", and "The Fires of Spring", four sweeping historical novels that take as their subject the earth-centered, Goddess-worshiping cultures of Neolithic Europe.  In 2012, her sixth collection of poetry, "Sugar Zone", won a PEN Oakland/Josephine Miles Literary Award.  Her first novel, "Immersion" (Shameless Hussy Press, 1972), was the first novel published by a Second Wave feminist press.  Long concerned with environmental issues, Mackey frequently writes about the rainforests of Costa Rica and the Brazilian Amazon.  In the early 1970s, as Professor of English and Writer-In-Residence at California State University, Sacramento, she was instrumental in the founding of the CSUS Women’s Studies Program and the CSUS English Department Graduate Creative Writing Program.  From 1989-1992, she served as President of the West Coast Branch of PEN American Center involving herself in PEN’s international defense of persecuted writers. The Amelia Peabody series is a series of twenty historical mystery novels and one non-fiction companion volume written by Egyptologist Barbara Mertz (1927-2013) under the pen name Elizabeth Peters.  The series is centered on the adventures of the unconventional female Egyptologist Amelia Peabody Emerson, for whom the series is named, and an ever-increasing number of family, friends, allies, and characters both fictional and based on historical figures.  The novels blend mystery and romance with a wryly comic tone, and at times also parody Victorian-era adventure novels such as those written by H. Rider Haggard.  The series was published between 1975 and 2010, with the final, posthumous novel (completed by Joan Hess) appearing in 2017. The interactive novel is a form of interactive web fiction.  In an interactive novel, the reader chooses where to go next in the novel by clicking on a piece of hyperlinked text, such as a page number, a character, or a direction.  While authors of traditional paper-and-ink novels have sometimes tried to give readers the random directionality offered by hypertexting, this approach was not completely feasible until the development of HTML.  For a discussion of paper novels that use a branching structure, such as Choose Your Own Adventure novels, see the Wikipedia entry on gamebooks. A・C・G・T is a Japanese animation production company, founded in 2001 by former Triangle Staff members.  It has been involved in the development of many series, predominantly contributing to other studios and adapting works based on light novels and manga.  It is a subsidiary of OB Planning, who handles executive production on many of its series.  A.C.G.T also works regularly with Genco, who at times provides executive production while A.C.G.T completes animation production. Chander Pahar (Bengali: চাঁদের পাহাড় , English: Mountain of the Moon ) is a Bengali adventure novel written by Bibhutibhushan Bandopadhyay and published in 1937.  The novel follows the adventures of a young Bengali man in the forests of Africa.  The novel is one of the most-loved adventure novels in the Bengali literature and is one of Bibhutibhushan's most popular works.  It spawned a media franchise. Emilia Marryat (later Emilia Marryat Norris; 1835? –1875) was a British author.  The daughter of author Capt. Frederick Marryat and his wife Catherine, she was known as a children's author who wrote adventure novels infused with moral lessons in the style of her father.  Some of her novels, including "Amongst the Maoris" (1874), are set in the Pacific and New Zealand.  "Amongst the Maoris" is the first novel to take the Waikato region of New Zealand's North Island as a setting.  Though two of her novels have Australian content, she is not known to have ever visited the country. The 39 Clues is a series of adventure novels written by a collaboration of authors, including Rick Riordan, Gordon Korman, Peter Lerangis, Jude Watson, Patrick Carman, Linda Sue Park, Margaret Peterson Haddix, Roland Smith, David Baldacci, Jeff Hirsch, Natalie Standiford, C. Alexander London, Sarwat Chadda and Jenny Goebel.  It consists of five series, "The Clue Hunt", "Cahills vs. Vespers", "Unstoppable", "Doublecross", and recently released, "Superspecial".  They chronicle the adventures of two siblings, Amy and Dan Cahill, who discover that their family, the Cahills, has been the most influential family in history.  The first story arc concerns Dan and Amy's quest to find the 39 Clues, which are ingredients to a serum that can create the most powerful person on Earth.  This series' primary audience is age 8–12.  Since the release of the first novel, "The Maze of Bones", on September 9, 2008, the books have gained popularity, positive reception, and commercial success.  s of 2010 , the book series has about 8.5 million copies in print and has been translated into 24 languages.  The publisher of the books is Scholastic Press in the United States.  Steven Spielberg acquired film rights to the series in June 2008, and a film based on the books was set to be released in 2016 but production has not yet started as of August 2017.  The series also originated tie-in merchandise, including collectible cards and an interactive Internet game.
Answer: five series