“This book pulls back the curtain on the work of criminal profilers. It debunks the myth of the ‘magical profiler‘ seen in TV dramas, turning the science of behavioral analysis into practical wisdom that anyone can use for safety and self-protection.”
— Official recommendation, WeRead

“This is more than a crime chronicle for those curious about the darker side of human nature—it’s a practical ‘late-night survival guide.‘ After reading it, you’ll start paying attention to which routes you take home at night and how to spot hostility in everyday situations.”
— Reader review

★ A dismemberment scene. The killer wiped away every fingerprint, every trace of DNA. But he left behind a pair of gold earrings. Why? This seemingly meaningless act became the case‘s only breakthrough.
★ The author is not a crime novelist, but a real forensic psychologist and law scholar. True crime is one of the fastest-growing categories worldwide. This book doesn’t manufacture suspense through fiction—it delivers the raw, gripping texture of real front-line work.
★ From the New York Bomber to serial cold cases, from murder scenes to the psychological signature of a dismemberment case—every case is real, every analysis is a field review. How does a criminal profiler actually work? This is how the seemingly magical profiling you see on screen is done, step by step, in reality.
★ “You can erase physical evidence—but can you erase psychological evidence?” When all physical traces are gone, behavioral evidence is the only way in. The TV adaptation is currently in production.
★ If you‘re fascinated by the FBI profiling records in “Mindhunter” and curious about the behavioral analysis in “Criminal Minds”—this book will show you how real profiling is done, step by step, on the front lines of criminal investigation.

Criminal profilers in TV dramas like Criminal Minds are often portrayed as near-magical figures—able to deduce a killer‘s appearance, occupation, and childhood trauma from nothing but a crime scene. But the real work is far more complex—and far more grounded.

This book traces the journey of a forensic psychology graduate student as he grows into a professional criminal profiler. Along the way, he faces his first major case—a crime so shocking it leaves him speechless. He picks apart the psychological signature left behind in a dismemberment case, where a pair of gold earrings becomes the key to solving the puzzle. He works on serial cold cases, identifying a pattern of sadistic behavior that ultimately leads to the perpetrator.

Author Lai Ji holds a postdoctoral degree in law and has spent over 15 years studying forensic psychology. He has participated in multiple high-profile investigations, providing technical support through criminal psychological profiling. He is no armchair theorist—he has worked the cases himself.

Structured around the author‘s journey from novice to expert, the book systematically breaks down the methods of criminal profiling—from FBI crime scene analysis to behavioral evidence analysis, from the consistency of thought and action to the core principle that “words and actions are code.” Every theory is illustrated with real cases, and every case reveals how profilers piece together a suspect’s psychological portrait from seemingly insignificant details.

“You can erase physical evidence—but can you erase psychological evidence?”—When physical evidence runs out, behavioral evidence becomes the only way through.

This is not a true-crime book for mere voyeurism. It‘s a “behavioral observation manual” for ordinary people—teaching you to recognize hostility, to sense danger before it’s too late, and to protect yourself from harm.

Lai Ji is a celebrated Chinese writer, screenwriter, and law scholar holding a postdoctoral degree. A faculty supervisor and a resident writer of the Bajin Academy under the Sichuan Writers Association, he has worked on the front lines of forensic psychological profiling for over 15 years.
He is a prolific author with 15 novels and 6 short-story collections to his name, spanning espionage, suspense, legal drama, science fiction, and adventure. Dubbed “one of the most adaptable authors for screen” by peers, 11 of his works have been adapted into films or TV series.
His notable credits include “The Hidden World” (adapted into the film “Absolute Loyalty”), and he also served as a script consultant for the Netflix-distributed series “Kunlun Shrine” and “South China Sea Return.”
A selection of his published novels includes “The Unseen Enemy” (adapted into a drama of the same name), “The Secret Files of State Security” (adapted into “X Bureau Secrets”), and “Daybreak,” which was praised by the renowned forensics writer Qin Ming. He also wrote the feature film “Money Fortress” (2024), directed by Danny Pang and starring Wang Qianyuan and Feng Shaofeng.

Prologue: A Forensic Psychology Novice‘s Unexpected Path

Chapter One: A Criminal Profiler’s Daily Work
1.1 What Is Criminal Profiling?
1.2 Finding the Profiler
1.3 Flying Wingman for Detectives
1.4 What Use Is a “Dragon-Slaying Skill”?
1.5 The Making of a “Super Detective”

Chapter Two: Stories from the Field—Are You Afraid of Death?
2.1 The First Major Case
2.2 The “Killer” Who Insisted He Didn‘t Kill
2.3 The Abyss of Desire: A Date on the Calendar
2.4 Sadistic Rape-Homicide and Serial Cold Cases
2.5 The Massacre Scene: The Most Visceral Discomfort
2.6 Gold Earrings in a Dismemberment Case: A Psychological Signature
2.7 Additional Notes

Chapter Three: Decoding the Invisible—The Code of Words and Actions
3.1 The Consistency of Mind and Behavior
3.2 You Can Erase Physical Evidence—But Can You Erase Psychological Evidence?
3.3 Psychological Stability: A Leopard Can’t Change Its Spots

Chapter Four: Deduction or Reconstruction? When Behavioral Analysis Becomes Science
4.1 FBI Crime Scene Analysis
4.2 Behavioral Evidence Analysis
4.3 Common Steps in Criminal Profiling Practice
4.4 A Test Case

Chapter Five: What You Draw—Your Words and Actions Reflect Your Inner World
5.1 Property Crime: Debt-Driven or Extreme Hatred of Wealth?
5.2 Indirect Profiling: The Young Man Who Stole a Pair of Nikes
5.3 Social Imprinting: A Surgeon‘s Incision vs. a Butcher’s Knife

Chapter Six: Why Does Crime Exist—An Inescapable Question
6.1 Born Criminal and Lombroso
6.2 A Mirror of Society
6.3 Dynamic Situations: Imbalance vs. Loss of Control

Chapter Seven: The Scale of Crime Dramas—Effects That Shape Criminal Psychology
7.1 The Path of Justice in “Police Story” and “SPL”
7.2 Rational Judgment in “Operation Mekong”
7.3 “Infernal Affairs”: Back to the Starting Point

Chapter Eight: The Future of Criminal Profiling
8.1 Will Criminal Profilers Become Extinct?
8.2 The Challenge of AI and Big Data
8.3 The Power of the Present

Epilogue: Why Keep Going? To Speak for the Victims