Two women who stabbed and shoved their victim in a car boot have received lengthy jail terms for their "extreme" violence from a judge who said the crime "almost beggars belief".
Nisha Phillips was kidnapped from a Claymore home in Sydney's south west, in February last year after she was stabbed in the knee and thigh by then-24-year-old Kayley Ketley while sitting on the couch.
Ms Phillips was later shoved in the boot of her own car as Ketley's co-offender, then-18-year-old Latia Henderson, took the driver's seat in an ordeal that lasted about five hours.
Campbelltown District Court heard the initial stabbing followed an argument over music in the car and a trip to McDonald's while Ms Phillips was driving.
According to the agreed facts, after stabbing Ms Phillips, Ketley declared: "I'm going to make you squeal like a pig, I just need to let it all out."
The two kidnappers left but when they returned, Ketley said to the bleeding victim: "Oh, you're still alive, what a shame."
Ms Phillips was then forced into the boot and driven south as she used a drawstring as a makeshift tourniquet.
She was stabbed again when the car stopped at Campbelltown, and the pair later searched for directions to Belanglo State Forest.
In sentencing, Judge Jennifer English said that forest was "a location which has a sinister connotation".
Ms Phillips used her fingernail to unscrew the tail light before waving her hand to motorists who then alerted police, bringing the kidnapping to an end.
Judge English said neither of the offenders rendered help to their victim at any stage.
"It almost beggars belief that two women would treat another young woman in this way," she said.
"The violence was extreme and continued over a considerable period."
During their trip, the two women recorded videos as they listened to hip hop music, as Ms Phillips lay terrified in the boot, at times passing out.
Ketley pleaded guilty to charges including kidnapping, causing grievous bodily harm, and reckless wounding.
Henderson admitted to kidnapping in company, but claimed Ketley was intimidating and she was concerned she would do something to her if she called for help.
Judge English rejected that claim and noted the videos recorded in the car did not appear to show someone under duress.
She handed Henderson a maximum sentence of seven-and-a-half years, with a non-parole period of five years.
Ketley was sentenced to a maximum of 11 years with a non-parole period of six years and seven months.
The judge noted Ketley was "no stranger to the criminal justice system", having previously served time behind bars for armed robbery.
She once vowed that it would be her "first and last time" in prison, but the judge said she had re-offended "in the most violent of ways".
Henderson was taken into custody after last week telling the court she was "absolutely disgusted" in herself and "extremely remorseful".
"She (Ms Phillips) didn't deserve that," she said during a sentence hearing.
Henderson, who now has a 15-month-old daughter, also admitted to leaving her grandmother's residence to use the drug ice before her court hearing, but declared she wanted to be "a better person".
In a letter to the judge, Ketley said she was "regretful of my actions" and recognised both the physical and psychological pain she inflicted on her victim.
She wrote that she was "ready to accept full responsibility" for her actions.