The Naturals Series in Order includes five full-length novels and the novella Twelve. For the simplest reading order, start with The Naturals and continue through Killer Instinct, All In, Bad Blood, and Dangerous Impulses before finishing with Twelve.
Publication order places Twelve before Dangerous Impulses, but I recommend saving the novella for last on a first read. Dangerous Impulses begins eight months after Bad Blood, while Twelve jumps ahead to Cassie at age twenty-three, so this order keeps the main teenage storyline together.
For a look at Barnes’ full bibliography, check out my complete Jennifer Lynn Barnes books in order guide.
Jump to:
- The Naturals Series in Order
- How the Naturals Books Connect
- The Naturals Boxed Sets and Special Editions
- Who is Jennifer Lynn Barnes?
The Naturals Series in Order
This is the simplest current reading order for someone starting the series now:
- The Naturals (2013)
- Killer Instinct (2014)
- All In (2015)
- Bad Blood (2016)
- Dangerous Impulses (2026)
- Twelve (2017) (Novella)
The first four books should always stay in publication order. They follow one continuous stretch of Cassie Hobbes’s life in the FBI’s Naturals program, and each novel carries forward personal mysteries, relationships, and consequences from the last.
Twelve is the only wrinkle. Strict publication order places it after Bad Blood and before Dangerous Impulses because the novella was released in 2017. That remains a valid order, especially for readers who already finished the original series years ago. For a new reader, though, I prefer the sequence above. It keeps the teenage storyline together before making the much larger jump into the characters’ future.
Dangerous Impulses is officially the fifth full-length novel, not a prequel or a spin-off. The publisher describes it as a new installment rather than a series finale, so there is no confirmed final-book status beyond the six works currently announced.
How the Naturals Books Connect
The Original Four-Book Arc
The Naturals introduces seventeen-year-old Cassie, who can read people by piecing together details most others miss. The FBI recruits her into a classified program for teenagers with unusual crime-solving abilities. She joins fellow profiler Dean, emotion-reader Michael, deception detector Lia, and statistician Sloane.
The opening case quickly becomes personal, and that pattern continues across the original four books. Killer Instinct pulls the team into a copycat case tied to Dean’s incarcerated serial-killer father. All In sends them to Las Vegas, where three public murders, a numerical code, and a break in the mystery surrounding Cassie’s mother collide. Bad Blood brings the long-running secrets about Cassie’s mother and the people behind her disappearance to a head.
Each novel has a central investigation, but these aren’t interchangeable case-of-the-week books. Character history and the larger conspiracy build from one installment to the next. My advice is to begin with The Naturals and avoid skipping around, even if one later case sounds more appealing.
Dangerous Impulses
Dangerous Impulses returns to the teenage Naturals eight months after the events of Bad Blood. The team is still dealing with the psychological fallout from its last case when it chooses what should be a happier challenge: bringing two of its FBI mentors back together before Christmas.
That plan leads into Special Agent Veronica Sterling’s past, a series of connected crime scenes, an unknown offender with a fixation on snow, and a cold case that is becoming active again. Because the story follows the emotional and investigative consequences of Bad Blood, I wouldn’t use it as a standalone entry point.
The 2026 publication date may make it seem as though Dangerous Impulses should come after Twelve. Within the story, it belongs first. Reading it in that position also avoids jumping from the teenage team to their adult lives and then back again.
Twelve
Twelve is a novella, not the fifth main novel. Cassie is twenty-three, and the original Naturals have taken over the program that once recruited them. Their work now includes identifying young people with similar abilities and handling cases that resist ordinary explanations.
The novella brings them to a coastal town in Maine, where twelve-year-old Mackenzie McBride believes a string of apparent teen suicides are murders. Her connection to the FBI reaches back to an earlier rescue, and the case forces the Naturals to confront pieces of their own childhood trauma.
You can understand the original four-book arc without Twelve, but it belongs in a complete Naturals reading order. I recommend treating it as the future-set coda and reading it last.
The Naturals Boxed Sets and Special Editions
The Naturals paperback boxed set contains The Naturals, Killer Instinct, All In, and Bad Blood. It also includes Twelve, which is printed at the back of Bad Blood rather than issued as a separate paperback in the box.
That 2023 set predates Dangerous Impulses, so it is no longer the entire announced series. I think it is still the most practical starting set for readers who want the original arc and a physical copy of the novella. You will need to buy the fifth novel separately.
The Naturals Deluxe Hardcover Collection is scheduled for October 13, 2026. It contains deluxe editions of the original four novels, but it does not include Twelve or Dangerous Impulses.
The individual deluxe hardcovers are alternate editions, not additional books in the reading order. The deluxe edition of The Naturals adds a new introduction and a behind-the-scenes question-and-answer feature from Jennifer Lynn Barnes, but the central novel remains the same first entry.
Who is Jennifer Lynn Barnes?
Jennifer Lynn Barnes is a #1 New York Times bestselling author of more than twenty-five young adult novels, including the Inheritance Games Saga, the Debutantes series, The Lovely and the Lost, and The Naturals series. She is also a Fulbright Scholar with advanced degrees in psychology, psychiatry, and cognitive science, and she earned her PhD from Yale University in 2012.
That academic background is especially relevant to The Naturals. Cassie and the other teenagers don’t have supernatural powers. Their abilities are heightened aptitudes for profiling, reading emotions, detecting deception, and interpreting statistical patterns. The mysteries are built around the different ways each character notices, processes, and applies information.
Looking for more books in order?
For more mystery authors and reading-order guides like this one, start with my Mystery Books in Order index.