GRAHAM Dwyer showed himself to be a "sadistic and brutal pervert with nothing on his mind but murder" in his text messages and documents, the Central Criminal Court has heard.
Prosecutor Sean Guerin SC asked the jury to take the accused at face value in what he alleged was an expression of an intention to kill contained in messages and stories recovered.
The architect brought Elaine O'Hara to the Dublin mountains to kill her after first coming up with a "carefully elaborated plan" which included finding an isolated location and a vulnerable victim, the prosecutor told the jury in his closing argument.
Mr Dwyer (42), denies murdering Ms O'Hara (36), at Killakee, Rathfarnham on August 22, 2012.
The prosecution maintains he killed her to satisfy his own sexual urge to stab a woman to death.
Mr Guerin told the jury to have regard for "Killing Darci" and "Jenny's First Rape" - graphic accounts of rape - and the series of text messages between Ms O'Hara and two pre-paid phones which he alleges were used by Mr Dwyer.
"I ask you to take at face value the unguarded and open expression of an intention to kill given by the accused man himself in the documents he wrote," Mr Guerin said.
"Those are the words of the accused man, if you are satisfied that it was Graham Dwyer who had these phones.
"The videos that he recorded were videos of his actions made by him, recorded by him, archived by him, the documents were the creation of his imagination, his desire, his fantasy. The text messages repeat those fantasies and set out a plan.
"All I am asking you to do is believe that when he showed himself in those documents and texts to be a sadistic and brutal pervert with nothing on his mind other than murder, he was telling the truth."
He disputed claims Ms O'Hara may have died by suicide, saying she was excited about the future. He also asked how she managed to dump her personal belongings in a reservoir, including half her clothing, and get to Killakee with no car.
Mr Guerin said the accused's wife, Gemma Dwyer, had also stated a spade found in Killakee was one from the family home.
Forensic tests showed the splatters of paint were similar in colour and composition to paint used on a fence in the Dwyer's garden and that all the paints in their shed that were tested had minor differences in their components, he added.