8 Book Series Whose Iconic Leads Became TV's Biggest Franchises

Image via Prime Video Published Aug 7, 2026, 6:45 AM EDT Chelsea Adelaine Hassler is an award-winning editorial, social, and creative director with two decades of media and entertainment experience and an all-consuming obsession with TV. A native New Yorker, she always completes the Sunday crossword, reads at least 100 books per year, and has Knicks season tickets. Sign in to your Collider account A great book can be carried by a protagonist with a strong motive, but only a protagonist with a strong sense of self can carry a great series. To exist beyond a single story, the core identity of a main character – their quirks, skills, and values – needs to drive them, not just describe them. It's what fuels their motivations and grants them agency; guided by a moral compass or a lived-in worldview, these protagonists act because of who they are, not what's happening around them. It becomes an anchor for readers, invested in seeing how their belief systems get tested, again and again. From Dexter Morgan to Alex Cross, some of television's biggest franchises are built around these literary protagonists. A main character with a fully-realized sense of self gives an adaptation an instant foundation, and years of source material grant the freedom to expand character arcs, develop new storylines, and evolve the anchor for a new audience. The best long-running book series aren't defined by their plots; they're defined by the protagonists who refuse to compromise their core identity, and that's what sustains these franchises, both on the page and the screen. 1 'Alex Cross' By James Patterson Appearing in 35 books over more than three decades, Alex Cross is James Patterson’s most enduring – and endearing – protagonist of all time. A brilliant psychologist and relentless detective, Cross is a widowed father with a close-knit blood and found family who works with the Washington, D.C. Metropolitan Police Department, the FBI, and in private practice to delve into the minds of dangerous criminals to solve complex cases. Driven by a moral code that prioritizes empathy and justice over vengeance, he’s dedicated to protecting his family and community, understanding what makes the bad guys tick, and bringing closure to victims. After two attempts at adapting Patterson's books into a movie franchise – Kiss the Girls and Along Came a Spider with Morgan Freeman, and Alex Cross with Tyler Perry – failed to take off in a meaningful way, showrunner Ben Watkins decided to take a different approach when creating his series for Prime Video. Cross stars Aldis Hodge as the crusading protagonist we've come to know and love, in a world we've come to recognize and with characters we remember, but with completely original mysteries that explore modern-day issues. And so far, it seems to be working out quite well; Patterson will release his 36th Cross book, The Family Cross, in October, and a third season of Cross is in the works for next year. 2 'Jack Reacher' By Lee Child Jack Reacher is a force to be reckoned with, in more ways than one. For 30 years, Lee Child – now writing alongside his brother, Andrew Child – has published a new bestselling Jack Reacher novel every single year, except for in 2010, when there were two. As a character, Reacher is just as relentless; he's a gigantic, nomadic ex-military police major who owns little more than a toothbrush, doesn't believe in following laws and conventions, but hits ten times harder and thinks ten times faster than anyone in a room. As soon as he steps off the bus in a new town, trouble always finds him; guided by a deep-rooted sense of fairness and a hatred of powerful people who exploit the weak, he spots an injustice and shifts into a stone-cold, calculated force of nature, seeking direct consequences to correct it. It's a true testament to the strength of Child's cerebral, solo-flying, wisdom-spitting protagonist that even when he was portrayed by an actor who is the literal opposite of everything that makes him Jack Reacher, Tom Cruise, he still came across as the same guy. It also makes it that much sweeter that Prime Video's Reacher cast the absolute perfect lead in Alan Ritchson, who brings a sense of humor, a little bit of cornball, and apparently a really excellent walk to the role. And there's no sign that Jack Reacher will be dropping off bestseller or streaming charts anytime soon, as the fourth season of Reacher premieres in August, the first season of spin-off Neagley drops in September, and the 31st annual Jack Reacher book, Chain Reaction, is due out in October. 3 'Harry Bosch' By Michael Connelly Michael Connelly first introduced 42-year-old Hieronymus "Harry" Bosch in 1992's Black Echo as an uncompromising, rebellious loner, haunted by war and hardened by his job as an LAPD homicide detective. Over the course of three and a half decades and 25 books, the now-former detective has aged in real time; presently in his mid-70s and keenly aware of his mortality, he's an investigator for hire who's begun mentoring the next generation of crime solvers. Yet Bosch still retains his core identity, the same stubborn independence, and continues to be fiercely committed to his personal code of "everybody counts, or nobody counts," a moral duty to work every case with equal persistence, regardless of who the victims are or what they've done in the past. After being established as one of the most beloved figures in contemporary crime fiction, Bosch became the heart of an equally beloved television universe. For more than 11 years, Titus Welliver appeared as the title character in Prime Video's Bosch and Bosch: Legacy, establishing a franchise that expanded with spin-off Ballard, which recently confirmed Welliver is set to reprise his role in the second season. There's also the forthcoming prequel Bosch: Start of Watch, which will see Cameron Monaghan take on Bosch's early days for MGM+ in a completely original story – not based on the books – that will serve as an official entry into the television canon. Connelly will serve as executive producer, and his 26th Bosch book, The Hollow, is due out in October. 4 'Will Trent' By Karin Slaughter Karin Slaughter's 12-book Will Trent series is told in alternating third-person voices, making her eponymous protagonist not just a lens on his world, but a character we experience within it. A survivor of severe childhood trauma in the Atlanta foster care system, Trent carries the full weight of its emotional and physical scars as well as functional illiteracy due to untreated dyslexia. The hyper-observational skills developed to combat it, combined with a deep internalized desire to bring order to chaos, have led him to excel as a special agent with the Georgia Bureau of Investigation. Motivated by an overwhelming need to protect others from being overlooked by the system, he goes well out of his way to ensure the comfort and safety of the vulnerable, and to get justice for those who deserve it. Ramón Rodríguez leads the cast of ABC's Will Trent, which takes a significantly lighter tone than the books and loosely adapts them to follow a case-of-the-week format that combines new storylines with existing literary elements. Trent himself is softer, less mired in the heaviness of his trauma, but his core identity and what makes him so compelling as a protagonist is retained beneath the surface-level tweaks that make him more approachable. Rodríguez does a masterful job of bringing Trent's trademark vulnerability and meticulousness to life in an altogether different yet equally impactful way in the series, which was recently renewed for a fifth season. 5 'Kay Scarpetta' By Patricia Cornwell Patricia Cornwell drew inspiration from a very real place when she created the character of forensic pathologist Kay Scarpetta, basing her on Dr. Marcella Farinelli Fierro, the first female chief medical examiner of Virginia. Brilliant, analytical, and poised, Dr. Scarpetta embarked on a career in medicine after losing her father to cancer at a young age, seeking rigorous, clinical truth in the face of death. Believing the body never lies and motivated by a profound need to give the deceased a voice and ensure their dignity, she leans heavily into hard data, physical evidence, and advanced forensic science technology to meticulously piece together the events of even the most complex criminal cases. Liz Sarnoff's Prime Video adaptation, Scarpetta, uses a dual timeline to show the same group of people, led by the title character, solving parallel crimes in two different eras, contrasting the scientific advances and investigative methods of the 90s with the present day. The modern cast is led by Nicole Kidman, supported by Jamie Lee Curtis, Bobby Canavale, and Simon Baker; the younger cast is led by Rosy McEwen, supported by Amanda Righetti, Jacob Lumet Cannavale, and Hunter Parrish. Each season uses two of Cornwell's 29 books in the series as source material, so it's a good thing she's slated to release the 30th book, Rapid and Fatal, early next year – and since it's in production right now, hopefully we'll be getting season two of Scarpetta ​​​​​​not too long after. 6 'Colter Shaw' By Jeffrey Deaver A newer protagonist among a group that's been around for decades, Jeffrey Deaver first introduced reward-seeker Colter Shaw in 2019. Over five books and a handful of short stories and novellas, the survivalist-turned-tracker has roamed the country in his RV, assisting in criminal investigations and locating missing individuals wherever there's cash to be found. Shaw is haunted by the mysterious death of his eccentric father, who raised him in an isolated compound in the wilderness and taught him the radical code of self-reliance, risk assessment, and rules of survival he strictly adheres to, so when he's not chasing down the answers to unsolved crimes, he's investigating the dark secrets his own family may or may not have left behind. Ben H. Winter adapted the series into Tracker for CBS, which stars Justin Hartley as a far more charismatic Colter Shaw and leans away from Deaver's deep-dive, sprawling mysteries and towards a more procedural, crime-of-the-week format. Despite shifting the focus to original cases better suited to an episodic format, and introducing a support team where he's a through-and-through lone wolf in the books, Shaw remains spot on with his mysterious literary identity. What made him so compelling on the page has been amplified on the screen, so it'll be interesting to see how, after revealing the facts of his father's death last season, Tracker adjusts Shaw's motivations to drive the action when the show returns for its fourth outing in October. 7 'Ryanverse' By Tom Clancy The oldest protagonist on this list needs little introduction, as the late Tom Clancy's Jack Ryan has been one of the most globally iconic main characters for more than four decades. The former Marine and Wall Street trader rose through the ranks of the CIA from analyst to operative to Deputy Director, took a brief detour as a history professor, and climbed up the government ladder as NSA chief, Vice President, and even President of the United States. Ryan has done it all, but the reluctant hero is always driven by a deep sense of patriotic and civic duty, and a hardwired moral compass that compels him to act in the face of imminent danger, as his brilliant analytical mind can never let a pattern or anomaly go unnoticed. Jack Ryan has been played by everyone from Alec Baldwin and Harrison Ford to Ben Affleck and Chris Pine on the big screen. But it's John Krasinski who had the time to fully embody the evolution of his character over four seasons of Prime Video's Jack Ryan and follow-up film Jack Ryan: Ghost War, and delivers what's arguably the best iteration we've seen to date. Though these adaptations take little from the book series by way of plot, largely due to the need to modernize the stories and update the approach to fit the current-day climate, Ryan is virtually identical to the character first introduced in the mid-80s. One of the strongest cases for an uncompromising protagonist providing limitless potential, we'll certainly be seeing Jack Ryan again and the Ryanverse again in the near future. 8 'Dexter' By Jeff Lindsay Dexter Morgan is a one-of-a-kind character. A blood spatter analyst who spends his free time as a vigilante serial killer, he's gripped by an insatiable urge to harm due to witnessing his mother's brutal murder at a young age, a homicidal compulsion – and later in the books, a supernatural being – known as the Dark Passenger. Dexter's adoptive father, Harry, noticed the Dark Passenger early on and recognized it could not be stopped but needed to be managed, so he developed a set of survival and moral rules for him to live by. Dexter is driven entirely by Harry's Code, which specifies he acts normally, plans carefully, avoids being caught, and must never kill an innocent person, and only those he has absolute proof have committed a murder or a violent crime. Michael C. Hall has portrayed a humanized yet still maniacal Dexter Morgan for the better part of two decades and has become virtually inseparable from the character. After Showtime's Dexter and Dexter: New Blood, attempts were made to shift the focus to Patrick Gibson as a younger version of the protagonist in the Paramount+ prequel Dexter: Original Sin, which lasted only a single season before the project was scrapped and Hall returned to reprise his role in the platform's Dexter: Resurrection​​​​. There were only 8 books originally, and while the core of Dexter remains, it's fair to say the television version is now the canon version of the character – and after exploring what that meant in its first season, Dexter: Resurrection has given him a second life and a new purpose.