A mother of four pleaded in vain for her life as she was viciously tortured with a machete before being shot twice in the head, the Brisbane Supreme Court has heard.
A de facto couple have pleaded not guilty to Tia Landers' murder but the court heard the woman on trial had boasted to an undercover policewoman that "we carved her up".
Ms Landers' body was discovered, wrapped in a blanket, in a shallow grave at Beerburrum State Forest near the Glasshouse Mountains in July 2014 with more than 30 wounds to her body.
John Edward Harris and Linda Eileen Appleton on Monday pleaded guilty to interfering with her corpse and two counts each of deprivation of liberty.
In his opening remarks to the jury, crown prosecutor Philip McCarthy said an undercover police officer was placed in Appleton's cell soon after her arrest.
"She will tell that officer: 'We carved her up, we chopped her up, we chopped her up with a machete," he said.
Mr McCarthy said Appleton then gestured two gun shots to the head.
He said Harris told a fellow prisoner that he fired the shots that killed her and he had had an affair with Ms Landers while Appleton was previously in jail.
He said two acquaintances - Jake McKenzie and Ryan Morgan - were with Landers when she was tortured and then murdered on June 16, 2014.
They will testify how she had pleaded for her life and they were ordered to clean up the blood before being driven home.
Mr McCarthy said prior conversations between the accused couple, recorded while Appleton was incarcerated over another matter, showed her feelings towards Landers.
"That scum slut probably f***ing stole them," he alleged Appleton told Harris during a phone call, referring to jewellery she believed Ms Landers had taken.
"I'm going to bust that bitch so f***ing bad, I am going smash her f***ing skull in."
Mr McCarthy said the post-mortem examination found wounds consistent with a machete to the ankle, thigh, shoulder, scalp and two "incise wounds to her vagina", however it was two gunshot wounds to her head that caused her death.
He told the jury a handgun and silencer found at their home matched bullet fragments in Landers' body, which was seriously decomposed when found.
Lander's mother Mary wiped tears from her face as she identified photos of her daughter's jewellery late on Monday.
She said she reported her daughter missing on June 19 after she failed to turn up on June 16 with "school snacks" for her four children who were staying with Mary.
The trial is expected to run for at least two weeks.
