The body of Moira Jones was found in Queen's Park in May 2008
The jury at the Moira Jones murder trial has been told "evil will not prevail" as the prosecution summed up its case.
Lord Advocate Elish Angiolini QC said there was "overwhelming" evidence that the accused, Marek Harcar, was responsible for Ms Jones' death.
However, defence counsel Paul McBride QC, has blamed another man, sex offender Jason Mulheron, for the crime.
Mr Harcar denies raping and murdering Ms Jones in a Glasgow park, last May.
Miss Angiolini's closing speech at the High Court in Glasgow lasted two hours.
She told the jury said: "It is difficult to imagine a more vile, wicked and barbaric murder witnessed upon Moira Jones.
"I ask you to return guilty verdicts based wholly on the evidence and not the emotion induced by the horror of the crime. Evil will not prevail."
The Lord Advocate earlier said Ms Jones was a woman in the "prime of her life" who had her "hopes extinguished" after returning to her flat on the night of 28 May last year.
She told the jury that the case against Mr Harcar was largely circumstantial.
Miss Angiolini added: "There is an overwhelming and compelling combination of circumstances which when taken together provide an irresistible inference that the man sitting in the dock is Moira Jones' killer."
But in his summing up, defence counsel, Paul McBride QC, told the jury that there were many reasons to doubt that Mr Harcar was guilty of the crime.
Miss Angiolini told the court how Mr Harcar had left the bedsit he shared with his flatmate that night claiming to "go out looking for a whore".
She went on: "Was he heading back to the flat when fate tragically intervened and he met Moira Jones?
"Or was he hanging around the street waiting to find what he wanted still angry, drunk or maybe even sexually frustrated?"
The prosecutor referred to CCTV taken from a bus which captured two individuals later walking near Queen's Park. Miss Angiolini called this a "chilling image".
The court was told it could be inferred that Ms Jones was marched towards the park before being attacked.
The Lord Advocate then spoke about the evidence of dog walker Steven Hanson, who heard a female scream that night and saw a man staring into a holly bush at the park.
Ms Jones' battered body was later found about 300 metres away further into the park.
Miss Angiolini said: "How she got there is not known. It must have been the most cruel and terrifying journey into the darkness away from the lights and away from the prospect of help."
She also told the jury that the DNA evidence against Mr Harcar was compelling including Ms Jones' blood on his leather jacket and his semen on her clothes.
Miss Angiolini said the "devastating" evidence of semen reduced the suggestion that he did not leave the bedsit that night as "utter nonsense".
The QC also dismissed the claims made by Mr Harcar that three other men were responsible.
Miss Angiolini said there was no "reliable evidence" that sex offender Jason Mulheron was the killer.
She said two brothers who stole and fraudulently used Ms Jones' credit cards were "scavengers" and not murderers.
But in his closing speech, defence counsel Mr McBride continued to point the finger at a serial sex offender, Jason Mulheron.
Queen's Park was closed after Ms Jones' body was found
He said Mulheron's previous attacks were similar to the attack on Moira Jones and that he had already confessed to the crime.
He went on: "That little weed (Mulheron) who stood there in the bright lights of this court looking surprised at the questions being asked is a far cry from the raging, drunk rapist on the southside.
"That little weed has ruined people lives and does not give a damn."
He added: "What do we know about him in relation to Miss Jones? He lives in the same area, attacks in the same area and is someone who clearly continues to want to rape women and kill if required.
"He has made an admission (to the murder), doesn't have an alibi and has got his girlfriend to lie for him.
"However it is not him sitting in the dock, it is Harcar."
Mr McBride also told the jury to be sceptical when considering DNA evidence.
He said scientists can only give a probability, and that DNA can only be used as a tool alongside other evidence.
Judge Lord Bracadale, will address the jury on Wednesday before it retires to consider its verdict.
It is claimed that Mr Harcar forced Ms Jones across the park against her will before he repeatedly punched, kicked and stamped on her head and body.
He is then said to have repeatedly struck her on the ground, forcibly removed her clothes, compressed her neck, pinned her to the ground and raped her.
Mr Harcar is also alleged to have murdered the businesswoman, who is originally from Staffordshire, and stolen from her.
He is then accused of attempting to defeat the ends of justice by fleeing to the Czech Republic and Slovakia between 1 and 18 June last year.
Mr Harcar has lodged defences of incrimination and alibi, blaming three others for the murder of Ms Jones.
The trial, before Lord Bracadale, continues.