Whoever Fights Monsters: Summary & Review

whoever fights monsters book cover

Whoever Fights Monsters (1992) talks about the psychological profiling of serial killers from the point of view of Robert Ressler, the man who coined the word “serial killer”.


For this Whoever Fights Monsters summary, I will skip the gory bits of Ressler’s crime descriptions and focus on the information that is more relevant from a psychological and psychiatric point of view.

#1. Sexual Maladjustment At The Root of All Serial Murderers

Sexual homicides are sexual in nature, but it’s important to notice that sexual homicide doesn’t necessarily mean that the murderer has had sexual intercourse with the victim (some of the murderers weren’t even able to have sex with the women they killed)

The author says that serial murderers are characterized as sexual homicides because sexual maladjustment is at the root of all of them.

Ressler says:

Sexual maladjustment is at the heart of all fantasies, and the fantasies emotionally drive the murderers

#2. Sexual Murderers Profiling

The most common profile for sexual homicides is: white, male, intra-racial (white on white or black on black), and in their 20s or 30s.

Ressler says that sexual murderers have troubled relationships with women.
They are unable to have and maintain mature, consensual sexual relationships.

Nearly half of their interviewees reported, never having had a consensual sexual relationship.
They were aware it was not normal and resented it.

Serial Killers Are Driven by Their Fantasies

Serial killers, the author says, are obsessed with fantasies.

They have unfulfilled experiences that become part of their fantasy and push them on toward the next killing.

#3. It Takes Time to Develop Psychosis Which Leads to Serial Murdering

The author says that homicides do not start earlier because it takes some time to develop full-blown psychosis, which eventually tips the scales in the killers’ minds.

Paranoia-schizophrenia usually manifests in the teenage years, and then it takes 8 to 10 years to reach that level of psychosis.

The author says that telltale signs like setting fires, animal cruelty, and assaulting teachers start in adolescence, but the mindset starts earlier.

#4. The Problems Start Early

The author says that behaviors that are precursors to sexual homicide have been developing since childhood.

Most sexual murders come from troubled families, with poor relationships with their mothers and are devoid of love and affection. 

As children, they were not socialized into proper and non-proper behavior.
Importantly, they are also not rescued in the next developmental phase of pre-adolescence, and at the age of 8 to 12, their environment either did not improve or got worse.

Fathers in this pre-adolescent period are missing. 

#5. Body Types Can Help With Profiling

Ready for a shocker?

Here it comes.

Cesare Lombroso, the early sociologist who said that criminals were more likely to be short, was ridiculed by my colleagues during my studies as a sociologist.
Well, Lombroso wasn’t right, but he wasn’t 100% wrong either.

Indeed, one of the most controversial assertions in Whoever Fights Monsters for today’s standards is the correlation between body types and the likelihood of committing crimes.

Robert Ressler says that it’s simple logic: introverted schizophrenics don’t eat well. 
They don’t think in terms of nourishment and they skip meals. They also don’t care about their appearances.
And the natural consequence is that they are scrawny and disheveled.

This paper also shows a correlation between crime and height, albeit remember that it’s not anything about “height genes”, but probably more a question of having fewer labor market opportunities.

#6. Organized VS Disorganized Offenders

Whoever Fights Monsters differentiates between organized and disorganized offenders.

Disorganized offenders are usually devoid of normal logic and tend to be less calculative and less calm when they’re in danger of getting caught.
They often don’t drive, and if they do, their cars tend to be in very poor condition.
They don’t think in terms of hiding pieces of evidence.

Organized murderers plan their crimes and even get better with time. They tend to fit better into societies and have better social skills.
They drive their own cars, and they can lure victims to their places with a false feeling of safety. 
Organized murderers are sometimes successful with women and have a string of sexual relationships, but they can’t hold relationships for the long run. And they have tremendous anger towards women (also read: toxic masculinity) and, often, towards society and people in general because they feel they have been mistreated.
Charles Manson, for example, believed it was society that held him down, or his songs would have been tremendously popular.

The disorganized murderer kills on the spur of the moment, while the organized one premeditates and seeks to increase his erotic satisfaction by keeping the victim alive.

The disorganized criminal was the kid that nobody remembered in school and was always quiet, with the neighbors thinking he was “Mr nice guy“.
The organized one was the bully, the clown, or the ones who fight in bars. They escalate conflicts quickly and often lose jobs because they provoke their colleagues or superiors.

 Disorganized criminals act out of their mental illnesses, and the pre-crime situational stress is often absent (more on it below).

#7. Criminals and Power Dynamics

Power and the search for power is a major motivators behind many sexual homicides.

Charles Manson, for example, played the Messiah for the people around him.
He was going to usher in a new era.
Manson renamed Charles Wattson “Tex” because there could be only one Charles in the Manson family.

And the rivalries between Manson and Wattson, another male member of Manson’s family, were a major factor in the dynamics of the murders.

Manson said that his biggest mistake was to “let that SOB Wattson have too much power in the family”, and Wattson was also murdered to elevate himself in the family’s power structure.

“Me Or Nobody” Frame of Mind

I also found telling the story of a murderer who, in prison, was taking care of a sparrow.
He loved the sparrow.

But when the guards told him the sparrow had to go, he threw it into the blades of a fan.

He still loved the sparrow, but he said, “if I can’t have it, nobody else can”.

This is another typical mindset of abusive men.

Fear Games Psychopaths Play

Robert Ressler tells the story of an interview he was having with a dangerous serial killer. 
When he buzzed for the guard to come, nobody showed up.

And the prisoner had a field day scaring Ressler about how easily he could kill him.

That reminded me of “The Psychopath Whisperer“, which I also highly recommend and where the author also details similar power games the psychopaths enjoyed playing.

My Note:
The author used a very bad approach there from a persuasion point of view.
He started arguing with the prisoner, saying that it would not be good for him to attack him and that he could defend himself.

That’s bad because it led the criminal to convince the author (and himself) that he actually could.

You don’t want to start a race where a serial killer wants to prove to you that he can kill you.

#8. Manipulation and Stockholm Syndrome

Robert Ressler explains that some murderers’ profiles are highly manipulative and very good at it. 

One FBI agent started passing information to a serial killer and maneuvered to be the only one with full access to the murderer. 
When the murderer was finally executed, the FBI agent was lost and disoriented, like he had lost a family member.

For more on manipulation techniques read:

Manipulation: Techniques, Strategies, & Ethics

Charles Manson Manipulation

Ressler also devotes much attention to Charles Manson and how he manipulated his followers.

Charles Manson admitted to giving the hippies around him what they wanted to see.
He became what they wanted, he “held a mirror in front of them”.

At the end of the interview, Manson asked Ressler to give him something to show the other inmates that he wasn’t talking to an FBI agent just out of good-heart.
Because that would lower his status among the other inmates.
Ressler gave him a pair of sunglasses, and he felt sure Manson was going to fabricate a story around it to lead the other inmates on.

Charles Manson was a typical cult-leader schooled in dark psychology:

Dark Psychology: 7 Ways to Manipulate People

#9. Other Important Traits of Serial Killers

  • Intelligence is not a predictor; it can be either lower than average or above
  • Mostly males (women serial killers kill on a spree and not sequentially)
  • Early traumas contribute, but not all rapists and murderers have been assaulted
  • The key differentiator is the development of perverse thought patterns
  • Kinky fantasies that mix sex, death, violence, molestation, dominance, revenge, control
  • The fantasies have strong visual components
  • While with most people’s fantasies, both partners have a good time, deviant fantasies correlate pleasure with the partner’s danger
  • Many serial killers keep objects (or body parts) that remind them of their victims
  • Once the first murder takes place he crosses a line and usually, there is no coming back: fear mixes with excitement and when he’s not caught right away he feels safer in killing again
  • The fantasies often don’t go away and it’s not easy to safely re-instate serial murderers into society
  • Not all schizophrenics are dangerous: most are not. But many serial killers are paranoid schizophrenics
  • Lie detectors are not reliable with psychopaths 
  • Many like to use the colors, shapes, and trappings of authority to control their victims
  • Overly cooperative behavior can be a warning sign as the murderer tries to pry information from the police to remain one step ahead
  • There is usually a sudden event or loss that precipitates the attacks (loss of a friend, unemployment, etc.)

#10. Would Bundy Stayed “Normal” Without Precipitating Factors?

Intriguing question.

Some people said that Bundy would have never become a serial murderer if he hadn’t had financial problems and if he was able to continue law school.
He would have become an aggressive lawyer spending money on hookers and entertaining more manageable forms of kinkiness.

But Kessler says that killers like Bundy would have eventually stepped over the line even without any precipitating factor.

Bundy talks about “overcoming social inhibitions” of church and socialization here:

I wouldn’t personally trust Bundy too much on whatever he says.
He has often been described as highly manipulative and a sociopath (or psychopath, the diagnoses were not precise).
But he likely had a mix of several different pathologies and didn’t have strong feelings of guilt to begin with. He personally bragged of “not having to deal with guilt”.

I would agree with Kessler that he eventually might have overstepped the line whether or not there was a precipitating event.


Ressler on his first interview with a serial murderer:

But it was his eyes that really got me. I’ll never forget them. They were like those of the shark in the movie “Jaws”: no pupils, just black spots. These were evil eyes that stayed with me long after the interview. 

And of course, the main quote:

Whoever fights monsters shall see to it that in the process he does not become a monster. And when you look into the abyss the abyss also looks into you.

whoever fights monsters book cover

Applications For Profilers

  • Don’t let “blank slate theories” pollute your ability to understand people and psychology

Whoever Fights Monsters shatters the idea that people are all the same and that the environment is what makes all the difference.

No, certain genders, races, and age groups are more likely to commit crimes. 
The author even says that certain body types are predictive.

  • Listen non-judgementally but don’t overdo it

The author explains how to win the trust of convicted murderers to let them speak freely.

He says you should be non-judgemental, but without overdoing it. When they talk about dismembering victims, don’t go overboard to make a big show of how many times you’ve seen that. 
Just stay normal without making a big show.

  • Ask good questions

Ressler talks about journalists and agents going after the famous serial killers just for being able to say they spoke to Charles Manson or to make a scoop.

He says these journalists often don’t get valuable information because of the silly questions they ask.
Ressler says he could see Manson losing all respect for a journalist when the journalist asked: “what does it feel to cut a man’s ear”.

Much better, Ressler says, would have been to ask what reasons Manson had to cut the victim’s ear.


I think Whoever Fights Monsters is an important book to read for all psychologists and psychiatrists, but it’s not very scientific:

  • Confirmation Bias on Profiling

I have a certain feeling this book promotes a lot of confirmation bias and over-confidence in the profiling abilities of FBI detectives (starting with Robert Ressler himself).

Ressler does not shy away from bragging about how good his profiles were, yet he does not say talk nearly enough about all the times they were wrong.

I would have preferred a more scientific look into this: how reliable is profiling?
How often were they wrong VS right? 

  • Profiling Data With Absolute Numbers is Misleading

The profiling that the author espouses, for example saying that it’s mostly white males, might lead people to the wrong conclusions.

For example, it does not take into account that the US overall population has more white males than, say, white Asians.

  • Big Mumble Jumble Lacking in Structure

I didn’t find the profiles to be very enlightening. The author should have used better categories in my opinion.

First, he says they all had trouble in childhood, then he says “not all rapists and murderers” suffered early traumas, then again he says it’s all about the fantasies.
And later he goes back to revisit the paranoid schizophrenics that he mentions at the beginning of Whoever Fights Monsters.

They’re all true, of course, and they often overlap.
But if he had used better categories and a better structure it would have been much clearer for the students who seek a better understanding of the mind of the serial killers.

  • Lacks Deeper Analysis of Psychopathy/Sexual Maladjustment Cross-Over

I wish the author had gone deeper into an important question: the overlap between psychopathy and sexual maladjustments.
Because I suspect there are people with violent fantasies who don’t act on them. 
So it’s only people who don’t have internal inhibitors who act on the fantasies.

Kiehl for example says:

Serial killers like Ted Bundy would meet criteria for psychopathy and they also have paraphilia, a sexual-based disorder like sadism. 
The drive to kill comes from the latter. 
The lack of emotions, empathy and guilt comes from psychopathy.

What I found lacking in Whoever Fights Monsters is the analysis of this overlap.

  • Bragging tone

Finally, Robert Ressler writes Whoever Fights Monsters with quite a bragging style.


Whoever Fights Monsters sits in between an informational text a psychiatrist could read and a lighter text that laymen simply interested in criminology could enjoy reading.

If you want to learn more about the psychology of criminals I also recommend “The Psychopath Whisperer” by Kiehl.
The difference is that Ressler operates as an FBI agent and the serial killers could not talk freely of their misdeeds.
With Kiehl’s interviews instead, the criminals were free to talk -and brag– about all the murderers they weren’t being prosecuted for, which provides him with a vantage point over their minds.

In any case, Whoever Fights Monsters is a must-read for anyone interested in psychiatry, abnormal psychology, and criminology.

Also, I can highly recommend this read on “non-serial killer psychopaths” who also inflict much harm:

Psychopaths’ Sexual Strategy: Marauders of Sex

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Or get the book on Amazon

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