The Dark Descent of Joanna Dennehy

Every once in a while, a person comes along that has us asking whether psychopaths are made or if they are simply born that way.

To add to that debate is Joanna Dennehy.

Joanna was born in 1983 in St Albans, England, to loving and kind parents. Her mother was a shop assistant and her father worked in security, and together they provided a happy and stable home for Joanna to grow up in.

“She was very sensitive,” her mother later said. “If she stood on a worm or something, she would be really upset if it died - she used to take them to bed with her… She was a loving girl.”

Joanna got good grades at school and loved playing netball and hockey, but so much of that charmed and gentle life that had been all that Joanna had known had also changed by the time she’d turned sixteen. By then she had a twenty-one-year-old boyfriend named John Treanor and the two of them ran off together, leaving Joanna’s parents and Joanna’s old life behind.

Joanna was a teenager and she enjoyed having an older boyfriend that she could live unsupervised with. She could do whatever she wanted and didn’t have to answer to anyone, but only a year later Joanna would learn that some actions do have consequences.

At the age of seventeen, Joanna found out that she was pregnant. Far from defending herself and her behavior after hearing the news however, the pregnancy only seemed to tick Joanna off. Joanna didn’t want children and even though she decided to keep the baby, it didn’t look like that opinion was going to change any time soon.

“She came out of the hospital and the first thought of her mind is to get stoned,” her boyfriend at the time John Treanor later said, but Joanna actually ended up doing so much more than just getting high. Joanna began abusing both drugs and alcohol and she started self-harming.

About six more years of this went by and Joanna became pregnant again. This time, John saw the writing on the wall and walked with both the children once their second child was born.

Joanna then moved to Peterborough, where she continued to abuse substances and allegedly worked as a prostitute to fund her habits. It is possible that it was because of this work that Joanna’s opinions of men began to change, but what is clear is that by the age of twenty-nine, Joanna had simply had enough of them.

It first started with a brief arrest for theft. During interviews, it became obvious to the arresting officers that they were dealing with something far more than just a petty, aspiring criminal.

Joanna was admitted to a hospital for psychiatric treatment and it was there that she was diagnosed with OCD and antisocial disorder, otherwise known as psychopathy.

Joanna was now officially a psychopath, but once her treatment was over, she was released back into the public. It was only about a year after that that Joanna would make headlines across the nation and become known as one of the most evil women in Britain.

Things escalated with thirty-one-year-old Lukasz Slaboszewski. He and Joanna had only met in Peterborough a few days before, but Lukasz was already excited about their future prospects. He told his friends that he was heading off that evening to see a girl he was hoping would soon become his girlfriend, but, unfortunately for Lukasz, he was far off the mark.

Joanna and Lukasz spent the night drinking and then Joanna invited him to a home owned by her landlord. There she enticed Lukasz in and asked him to put on a blindfold. Lukasz eagerly agreed and once he had it on, Joanna pulled out a knife and began stabbing him.

One of those stab wounds pierced Lukasz’s heart and killed him.

Joanna then hid his body in a dumpster and went about her evening, but she could never come back from what she had just done. She could never undo killing Lukasz and she could never put the feelings that murdering someone had stirred up inside her back in the box.

Joanna knew that she wanted to kill again and she lasted only ten days before she gave into the urge to do so.

This time she struck closer to home.

For Joanna, part of the whole ritual was the thrill of the hunt; the drawing in and enticing of her victims. Targeting women was out of the question. They were likely mothers and Joanna could take mothers away from children, so it was men that she would go after.

Fifty-six-year-old John Chapman, one of Joanna’s housemates, fit the bill perfectly. Joanna flirted and seduced and she drew him into her room. There she toyed with him before turning to her tried and true. She told John to put on a blindfold and wait and then, once he couldn’t see her coming, she began stabbing him.

Joanna satisfied her urges by killing John, but instead of keeping Joanna satiated, this new murder only seemed to spur her on.

Only hours later and Joanna had her next fix in front of her: forty-eight-year-old Kevin Lee. Kevin was actually Joanna’s, and her previous murder victim John’s, landlord and Joanna already had him ensnared. Joanna was Kevin’s mistress. But even Kevin could have had no idea what awaited him when Joanna invited him in that evening, or even that his other tenant was already lying dead in that very same house.

Joanna got John into her room and then she played with him. She convinced him to put on a black sequin dress and then she told him to put on a blindfold. Kevin, like the others who had gone before him, never saw Joanna reaching for her knife. She stabbed her boyfriend to death and then she moved on to getting rid of the evidence.

The first thing that Joanna had to dispose of were the bodies piling up around her and to do that, she employed some unexpected tactics.

Shortly after she’d first moved to Peterborough years before, she’d met a man named Gary Richards who went by the nickname Stretch. Joanna called Stretch and asked him to help her move and discard the remains of the men she’d just killed.

And perhaps in one of the most bizarre twists and turns of this case, Stretch actually agreed. Stretch had fallen for Joanna all of those years ago and it looked like he simply couldn’t do enough for her. 

Along that same vein was thirty-six-year-old Leslie Layton who was someone that Joanna counted as a close friend. Certainly, it would seem close enough to ask for help in a time of crisis.

Joanna managed to convince not one but two people to help her dispose of the bodies and the three of them drove around Peterborough roads, looking for ditches to hide Joanna’s victims in.

Kevin would stand out amongst the bodies abandoned on the side of the road. The sequin dress had been just the start and his remains were arranged in a sexually explicit pose to hammer in the humiliation.

That took Joanna’s victim count up to three. She now had a plan and it was a cold and cruel one. Joanna was now determined to kill at least nine men before she was caught and the pressure was building. She’d gone from lasting ten days to giving into her urges to mere hours and time was ticking. 

She, Stretch and Leslie were driving back home from dumping Kevin’s body when Joanna snapped again. This time her victims weren’t her boyfriend, her housemate or the landlord she was having an affair with. 

They were two men out walking their dogs.

Joanna ordered Stretch to stop the car and then she pounced. She caught Robin Bereza in the shoulder and chest with her knife and then she turned on John Rogers. She stabbed John over forty times before fleeing the scene, leaving Robin and John to helplessly bleed out on the street.

Fortunately for these two victims, timely medical intervention saved both of their lives.

Back on her murder spree, Joanna then found herself the target. The investigators cornered her after finding Kevin Lee’s remains, but almost unbelievably, Joanna managed to escape with Stretch before they could arrest her.

She was on the run for two days before the authorities caught up with her, but, in another twist in this case, Joanna seemed to enjoy the attention. Instead of being angry or sad that she had been caught, especially before fulfilling her plan of killing nine men, Joanna seemed to find it funny.

Security footage of her arrest shows her laughing and flirting with the processing police officer. 

Perhaps she was still trying to entice a victim even at the very last moment.

At trial, Joanna pled guilty to all charges and was sentenced to life in prison with the recommendation that she never be released. Joanna is one of only three women in British history to have ever received this sentence, one of the other ones being notorious serial killer Rosemary West.

Joanna was actually placed in the same facility as Rose West, but Rose was moved after Joanna threatened to kill her too.