A jury trying two people accused of murdering a mother-of-three was told the case is the 'most obvious one of murder imaginable'.
Torbjorn, also known as Ian, Kettlewell and Julie Wass are accused of murdering Kelly Franklin in a street attack in Hartlepool.
Ms Franklin, 29, was stabbed more than 30 times in the chest and neck by Kettlewell, her former partner.
Wass drove Kettlewell to the area of the killing, and she drove him away from the scene afterwards.
In his closing speech to the jury at Teesside Crown Court, Jamie Hill QC said: "We know Kettlewell had exercised control over Kelly Franklin during their relationship.
"We have heard he is a man who has gone through his life blaming others,and failing to take responsibility for his actions.
"He blamed Kelly, and a social worker, for their children being taken into care.
"At the time of her death she was working hard on getting her children back.
"Kettlewell realised he was losing control of Kelly, so he thought if he couldn't have her, no one else will."
The court heard previously Kettlwell was obsessed with knives, and had threatened to stab both Ms Franklin and a social worker.
"Julie Wass knew of Kettlewell's state of mind that day," said Mr Hill.
"She knew he was wound up, and she knew of the previous threats.
"The stabbing of Kelly by Kettlewell was the most extreme act of 'if I can't have her, no one else will'.
"Kettlewell was ably assisted in that by Julie Wass.
"She was with him for large parts of that day, she knew he was brooding over Kelly, she helped him find her, and she acted as his getaway driver.
"We say this is the most obvious case of murder imaginable."
Kettlewell admits stabbing Ms Franklin, but claims he was suffering from an abnormality of mind at the time which would make him guilty of manslaughter by diminished responsibility.
Two psychiatrists told the court Kettlewell does have a mental health condition, but it is not serious enough to amount to the legal definition of diminished responsibility.
"Put simply, both doctors say he was crackers," Richard Wright QC, for Kettlewell, told the jury.
"If you listen to the prosecution this is an open and shut case, and you may be wondering if we are wasting your time.
"We recognise that as a defence team we have work to do, but we urge you to be cautious about viewing everything through the prism of the few seconds of that horrific stabbing.
"Mr Kettlewell lost control in that moment, but no one knows exactly why.
"Despite all the unpleasant things said about him, and he may be all of those things, the evidence suggests there was light and shade in his life.
"Despite all the bravado and bragging, none of the witnesses thought he would physically harm anyone.
"All we ask is that as a jury, you consider his case carefully and fairly."
John Elvidge QC, for Wass, said she had been 'imbued with knowledge' by the prosecution that she did not have.
"She did not know of his intention to stab Kelly Franklin, there is no evidence of that," Mr Elvidge told the jury.
"The prosecution cannot prove Mrs Wass knew Ian Kettlewell had a knife.
"She is a woman with no history of violence, no history of criminal offending of any sort.
"She had nothing to gain from the killing of Kelly Franklin.
"The criminal responsibility for the death of Kelly Franklin lies solely with Ian Kettlewell."
Kettlewell, 30, of Oval Grange, Hartlepool, denies murder on August 3.
Wass, 48, of Kipling Road, Hartlepool, denies murder.
She admits assisting an offender.
The case continues.