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The background to The Mayfly is the biggest crime in human history: the Holocaust.


It is a common mistake to dismiss the perpetrators of this crime as madmen and lunatics, although it’s easy to see why the mistake has been made: just reading about Josef Mengele’s fascination with twins is enough to take your breath away.


But Mengele was no monster in the traditional sense. He was reportedly handsome, educated, calm and tried to act paternally towards some of his captors. Some of them even called him ‘Uncle Mengele’.


But later he would select a twin, seemingly at random, order that he be taken for surgery, then castrate him.


Shockingly, it’s not even clear why such cruel experiments were carried out, other than the vague notion that it was something to do with Mengele’s research into the possibility of purifying the Aryan race through eugenics.


In the aftermath of the Holocaust, it was clear that the concept of evil had to be recalibrated.


The Mayfly is not just an exploration of evil; it is a story of how evil may or may not have genetic tendencies. Charlie Priest is constantly haunted by the crimes of his brother, William, the notorious serial killer. Is he, Charlie, capable of the same inhuman barbarity? What manner of fatalistic elements fused together to create two brothers so fundamentally different?


The concept of the evil gene has been much debated and the scientific community is split. There is some empirical evidence to show that Charlie might be right to be wary: one study in Denmark found that a person who has an identical twin with a criminal record is 50 per cent more likely than the average Dane to have been in prison himself, although this reduces to between 15 and 30 per cent for non-identical twins.


Back to the Nazis, when the German occupiers deported the entire Danish police force for several months, there was a notable rise in opportunistic crime – robberies and theft – but very little increase in violent or sexual offences. Equally, various studies over time have demonstrated that increasing prison sentences for certain crimes has little effect on the crime rate.


One might conclude from this that people either have the capacity to commit crime, or they don’t, and that the tendency to be delinquent might in some way be genetic.


Whatever the answer is, it’s clear that this possibility is now being taken seriously. In 2013, an analysis was carried out in the University of Connecticut of the DNA of Adam Lanzer, an American spree killer who, aged 20, walked into Sandy Hook Elementary School with a shotgun and murdered 20 children and six adults before turning the gun on himself.


There is no biological proof of the existence of an evil gene yet, but the implications of finding one are profound. Should people be punished for crimes that they have not yet committed?


Paradoxically, can we then legitimately reward or even recognise positive behaviour, if all the hero is doing is what he or she is biologically programmed to do?


And as for the idea of demon DNA, you’ll have to wait for a new Charlie Priest thriller to see that strange notion hauled to the surface for all to see.



About James Hazel:


Before turning his hand to writing, James Hazel was a lawyer in private practice specialising in corporate and commercial litigation and employment law.

He was an equity partner in a regional law firm and held a number of different department headships until he quit legal practice to pursue his dream of becoming an author.

He has a keen interest in criminology and a passion for crime thrillers, indie music and all things retro.

James lives on the edge of the Lincolnshire Wolds with his wife and three children.

For more info visit

Twitter @JamesHazelBooks


Evil Genes and Demon DNA

Guest post by James Hazel

author of THE MAYFLY




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