It was midnight on Monday the 11th of April, 2016. Fourteen-year-old Lucas Markham had set out for his girlfriend Kim Edwards' house on Dawson Avenue in the small market town of Spalding, Lincolnshire. In his backpack, rolled inside a black T-shirt, were four kitchen knives. When he arrived at the back of the house, he clambered onto the roof of a shed and knocked three times on her bedroom window. He waited, but before long he realised that Kim, who was also 14, was fast asleep. Lucas walked back home alone.
The following night he returned. Again, he knocked on the glass. Again, she didn't hear him.
The next night, Wednesday, Kim heard him knocking. Going to the bathroom, she opened a window to let him in. When he got inside, Lucas said: "Are you sure you want to do this?"
"I said yes," Kim would later tell police, "but then, in the end, I couldn't do it, so he did it."
Kim waited in the bathroom as Lucas crept towards her 49-year-old mother Liz's bedroom. As he left, Kim realised he'd veered slightly from their methodically-formulated plan. She whispered: "Take your shoes off."
Having reached the bed without waking his girlfriend's mother, Lucas proceeded to stab her a total of eight times. Two blows to Liz's throat almost completely severed her windpipe. As she woke up and struggled to defend herself, he stabbed her five times in her hands. He climbed on top of her, forcing a pillow over her face. He would later tell police that Liz had scratched his "face, back and bum" as she tried to break free.
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As they struggled, Kim came into the room. By now there was blood spattered across the bed and walls. Lucas told her to shut the door. As Kim approached the bed, her mother's flailing hand found hers.
"She was struggling," Kim remembered later. "She reached out her hand, so I grabbed it and kind of held it. As I realised it was her hand I instantly drew my hand back and got into a cradle position. I sat on the floor next to the door and said to myself, 'Breathe,' as I was about to have a panic attack. My legs were shaking. Then I walked back and forth and said: 'It's going to be OK, keep calm. It's going to be over soon.' After about ten minutes of putting his weight on her she was dead. She had kind of gone limp and wasn't struggling any more, but she was still making gurgling sounds. I think I said: 'Is she dead?'"
Lucas checked Liz's pulse. When they were sure she was dead, the two children went next door to the bedroom that Kim shared with her 13-year-old sister, Katie. Once more, Lucas stabbed her repeatedly in the throat before suffocating her with a pillow. Kim heard her sister's last words, a muffled: "I can't…" in what she called a "scary voice… all croaky".
The couple then ran themselves a bath to wash the blood from their bodies. When they were clean, they dragged Kim's mattress downstairs to put it in front of the television. Left to their own devices, they ate toasted tea cakes and ice cream. They had sex. They watched three Twilight films back-to-back. The tabloids would later refer to them as the "Twilight Killers".
They planned to commit suicide the following day at 2PM. Kim wrote a note that read: "I want Lucas and my ashes scattered at our special place. From Lucas and Kim, we don't give a fuck any more." However, when the appointed hour arrived they changed their mind. They watched a fourth Twilight film instead.
They remained in the house together for 36 hours. The police, having been alerted that the pair weren't at school, eventually broke in through a downstairs window. They found the couple lying together under a duvet.
The officers asked Kim where her mother was. She replied: "Upstairs."
They asked Lucas what had happened to her. He replied: "Why don't you go and see?"
The reason Lucas and Kim gave for doing what they did is remarkable most for its ordinariness. Kim believed that her sister, Katie, was her mother's favourite. She said that her younger sister "got all the fuss" and "took my mother away from me".
There had been an incident when Kim was eight where Liz had lost her temper and hit her in the jaw. Both Kim and Katie were subsequently taken into care and spent four months with a foster family before returning to their mother. Kim and Liz continued to argue. On the Saturday before the murders they had fallen out over Liz's reluctance to let Kim see the sisters' estranged father, Peter Edwards.
Kim later told detectives: "Ever since I was young I never got on with my mum. I knew she favoured my sister more than me. She said she didn't but I knew she was lying. They would talk together, and whenever I got into an argument with my mum, Katie would always take her side... Lucas just hates me being upset. He didn't like my mum or my sister for that reason. I got rid of the biggest problem that made me feel depressed, which was my mum. It was a relief."
Kim had first noticed Lucas in September of 2013, when he got in trouble for throwing a chair across the room in an English class at the Sir John Gleed school in Spalding. They became friends, and he asked her out over Facebook on the 23rd of May, 2015. He was often involved in fights at school, and at the time of the murders had already been expelled for disruptive behaviour. The couple planned their crime together, first in Kim's back garden and then at a McDonald's a 15-minute walk from her house. Kim would later tell police: "I've felt like murdering for quite a while." A former schoolmate, Adam Free, told The Mirror that Lucas had spoken about killing Liz, but that nobody had taken him seriously.
Child psychologist Dr Alice Jones is a Senior Lecturer in Psychology at Goldsmiths, whose expertise covers the development of antisocial behaviour and psychopathy in children. She says that children who kill often display a pattern of violent behaviour before murder, and believes there are signs which can indicate a particularly high risk of following through on the most serious threats. "I think it's kids who have this package of being aggressive but also who don't seem to care about other people's feelings," she says. "Lots of kids get into fights but can recognise that it was the wrong thing to do. They're capable of showing appropriate social behaviour towards other people. The kids I worry about are those that don't, who just don't seem to care about other people."
At Nottingham Crown Court in November of 2016, Lucas Markham and Kim Edwards were sentenced to life imprisonment. They are Britain's youngest ever double murderers. The judge, Mr Justice Haddon, drew particular attention to how little remorse the pair have shown for their crime, and the level of planning they put into it. "This case is, in many respects, without parallel," he said. "There was remarkable premeditation and planning – it was, on any view, substantial, meticulous and repeated. The killings were brutal in the form of executions, and both victims must have suffered terribly in the last minutes of their lives."
Both Lucas and Kim will serve a minimum of 17-and-a-half years in prison, although Dr Jones believes it is likely at least one of them will be inside for much longer. "I would be surprised if at least one of them doesn't get into more trouble during their incarceration," she says.
She makes her prediction based on the difficulty of successful rehabilitation for children who have acted on psychopathic tendencies. "Can they go back into society? I think it would be very difficult after doing something like that, which is so life-changing – especially for the girl, who has done this to her own family," she says. "I think, in general, for kids who have these kind of traits it's quite difficult to change the way that they behave overall. It's very difficult to make empathy happen in people. If you don't really feel empathy, it's hard for someone to persuade you to. It's a real biological thing. If you don't really feel fear and sadness, how on earth can you understand it in somebody else?"
However, Carol Anne Davis, the author of Children Who Kill, points to examples like Mary Bell and Bernadette Protti as evidence that, in some cases, children who kill can be rehabilitated as adults. "Lucas and Kim were only 14 when they killed, so their brains have yet to mature," she says. "Teens cannot control their emotions in the way that adults can, and they are wired to take risks and give in to peer pressure. By 25 they will have many more synapses – new connections in the brain – and could be entirely different characters. Much will depend on the relationships they form during their years in detention; a caring role model can make an incalculable difference."
Whatever happens to them, Lucas and Kim – still just 15 – will carry these heinous murders with them for the rest of their lives. So too will the family and friends of Liz and Katie. After seeing one of his own daughters convicted for the murder of the other, Peter Edwards bought the burial plot next to Katie's. He wrote on Facebook: "Got to say now I own the spot I can not wait to lay in it when the time comes."
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