Killer instinct: Meet Joanna Dennehy, the most dangerous woman in the UK

It means something when you’re the most dangerous woman in or out of prison. But the title of “UK’s most dangerous woman” didn’t go to Joanna Dennehy just for her actions out in the world. Her life in prison has been just as gruesome as her life on the outside. 

Best known for committing the Peterborough ditch murders, Joanna Dennehy has terrorized citizens of Cambridgeshire, England for years with her disgraceful acts. Now at HM Prison Bronzefield in Surrey, she’s continued her terroristic reign. But what caused her to be as evil as she is?

The woman with a vendetta against men

A teenage runaway, Dennehy left home at 16 and stayed on the streets throughout Cambridgeshire. With undiagnosed mental issues, until she was arrested, Dennehy ended up turning violent specifically towards men. Her end goal was killing nine men like Bonnie and Clyde, but she only killed three and injured two. 

The attacks in 2013, where three bodies were found outside Peterborough, are the crimes Dennehy was convicted for. A former boyfriend of Dennehy’s and two of her flatmates were found in ditches in towns outside Peterborough with stab wounds. 

Sometime later, Dennehy was driven to find two other random men walking around, attacking them. Both men survived their attacks, though one of them got their dog stolen by Dennehy. 

Why men?

Acquaintances of Dennehy’s have gone on record saying Dennehy specifically targeted men, refusing to kill women, especially ones with children. Ironic, considering Dennehy was a deadbeat mother of two herself. But she stuck to her truth, and all of her victims were specifically male. 

Dennehy used the murder as a form of entertainment for herself, saying that she needed to “get my fun”. After the first, Dennehy found murder to be moreish, and she got a taste for it after her first victim. With no shame, Dennehy pleaded guilty to the murders, receiving a life sentence for the crimes. 

Running the prison game

But she didn’t end her demonic ways when she went to prison. Dennehy would write to male fans of hers, trying to lure them in by giving them details of her crimes and her younger life. Her intentions were to lure them in and attack them during visiting hours or in some other way. 

Of course, she had no romantic interest in the men she charmed. Instead, she was infatuated with fellow prisoner Alexandra Crouzieres during her time at HM Prison Bronzefield. Even after Crouzieres was released, their relationship continued, with Crouzieres trying to sneak in a ring for Dennehy during one visit.

Even before she was tried for her murders though, Dennehy was causing issues in the prison system. Before her trial, Dennehy was sent to solitary confinement after a journal detailing a bloody escape plan was noted. This plot involved murdering a security guard and using his finger to fool biometric scanners in the prison. 

Playing the pity game

While in jail, Dennehy spent her time using her charm to try and play the game to get more attention. In recent years, Dennehy has had two suicide attempts, one in a suicide pact with her lover, and another on her own. 

Dennehy and her lawyer team also tried to argue that her human rights were violated being moved to solitary confinement before her trial. But her claim was rejected, saying that because of her violent nature and the crimes she was being charged with, it was necessary to protect other prisoners and herself. 

Dennehy may have a history of mental illness, but that’s no excuse for the crimes committed by her. There’s no reason anyone should pity a monster like Dennehy.

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