Two teenagers pre-occupied with violence, torture and death stabbed to death transgender teenager Brianna Ghey, a court heard.
Brianna, 16, was stabbed 28 times with a hunting knife in her head, chest, back and neck while in Culcheth Linear Park, near Warrington, Cheshire, in February this year.
The defendants, a girl, 16, identified only as X, and a boy, 16, identified only as Y, were both aged 15 at the time. Both deny murder.
Neither can be named by court order because of their age.
At the start of their trial the jury of seven men and five women were told they had made plans to kill other children before killing Brianna.
Girl X also liked to watch “dark web” torture videos and had become “obsessed” with Brianna, born a boy but who identified and lived as a girl, Manchester Crown Court heard.
Girl X, wearing a dress and grey cardigan and boy Y, wearing black trousers and shirt with a grey tie, sat in the dock listening as Deanna Heer KC opened the case for the prosecution.
Ms Heer said Brianna’s body was discovered by dog walkers Kathryn and Andrew Vize, at about 3pm on February 11 in the park near Warrington.
They also saw a male and female breaking into a run as they approached the body of a young woman lying face down in the mud.
Ms Heer told the court the body was that of Brianna, 16, a young transgender person, who had suffered a “sustained and violent assault”.
Ms Heer said there was no dispute that the male and female seen running away from Brianna’s body were the two defendants.
She added: “Nor is there any dispute that in the days and weeks leading up to that day they had discussed killing her.
“Indeed, it is accepted that Brianna Ghey was killed with a knife that belonged to boy Y, a knife which he told girl X he would be bringing with him that day and which he said was sharp enough to kill her.”
The jury was told each defendant denied murder and denied participating in killing Brianna.
Ms Heer said: “Each blames the other.
“The prosecution case is that whoever it was who delivered the fatal blow or blows, both defendants are equally guilty.
“Acting together, they planned and executed their plan to kill Brianna Ghey.”
Messages recovered from the phones of girl X and boy Y showed a “preoccupation” with “violence, torture and death” and recorded them discussing how they wanted to kill people they knew.
They also showed how, over time, they encouraged one another to think about how they would carry out the plan to kill.
In November 2022 they discussed killing a child referred to as boy M, the court heard.
In one message girl X said: “If I do end up killing boy M, I have a really sharp blade, the same one that Sweeney Todd uses.
“If we kill boy M can I keep some things, a couple of teeth and an eye.”
In early December, girl X sent boy Y a video which was apparently an advert for an underground site for people who like rape, snuff, torture and murder.
Girl X told boy Y: “I love watching torture vids. Real ones on the dark web,” the jury heard.
The court heard that on January 1, boy Y sent girl X a photo of a hunting knife and told her: “Spent my money. I bought a knife.”
Ms Heer said: “It was this knife, members of the jury, that was to be used to kill Brianna Ghey just six weeks after this image had been sent.”
The court was told that in December last year girl X messaged boy Y telling him she was “obsessed over someone” called Brianna but did not have feelings for them.
Girl X told him Brianna was trans, sounded just like a girl and looked really pretty, the court was told.
Deanna Heer KC, prosecuting, said that on January 23 girl X messaged boy Y telling him she had given Brianna ibuprofen gel tablets that “should have been enough to kill her”.
Brianna’s mother, Esther Ghey, recalled her daughter had been sick at about that time, the court heard.
They also spoke in messages about other people they wanted to kill and by January 26 had compiled a list of at least four people, as well as Brianna.
Girl X created a fake Instagram account to contact one of their targets, referred to as boy E, but it was blocked.
In a message read to the court, girl X told boy Y: “If we can’t get boy E tomorrow we can kill Brianna.”
Boy Y replied saying: “Yeah, it’ll be easier and I want to see if it will scream like a man or a girl.”
They discussed meeting Brianna and killing her at the park the following day, the court heard.
In one message, girl X said: “I want to stab her at least once even if she’s dead jus coz its fun lol.”
Ms Heer said girl X and boy Y did meet each other in Culcheth on January 28, but girl X told him Brianna said she could not come.
The trial, expected to last up to four weeks, was adjourned until Tuesday.