A John Travolta fantasist is facing life behind bars for the "horrifying" rape and murder of a teenage girl after evading justice for 34 years.
For half a lifetime, self-employed tiler James Warnock, 56, got away with strangling 17-year-old Yiannoulla Yianni in her own home in broad daylight, just half a mile from where he lived with his wife in north London.
The murder shocked the nation and led to high-profile police appeals which led detectives as far afield as Australia in their search for the killer.
But it was not until December last year that Scotland Yard got a "lucky break" when Warnock was arrested over indecent pictures of children.
His DNA was added to the national database and found to be a match for samples taken from Yiannoulla's body.
The divorced father-of-two, who was still living in the local community, tried to explain away the evidence by claiming to have had a secret affair with Yiannoulla, even though the teenager was brought up in a traditional Greek Cypriot family and never had a boyfriend.
Her family broke down in tears as a jury at the Old Bailey took just over two hours to find Warnock guilty on Thursday.
The verdict could only be reported after the defendant had admitted six charges of distributing indecent images of children in 2013 and 2015. He will be sentenced later for all the offences.
On August 13 1982, the victim, known as Lucy or Noodles, had been with her parents at their shoe repair shop minutes away from their Hampstead home.
Yiannoulla's mother, Elli, had sent her home to start preparing a leg of lamb for supper, saying she would join her soon.
She was playing the latest Patrice Rushen hit Forget Me Nots on the record player when Warnock knocked on her door at about 2pm.
A young man was spotted chatting with Yiannoulla on her doorstep, and 20 minutes later a neighbour heard a scream, jurors were told.
Her parents arrived home half an hour later to "a sight beyond their worst imagining" - Yiannoulla's partially naked body lying on their bed, prosecutor Crispin Aylett QC said.
Despite a high-profile public appeal, including a televised reconstruction featuring her sister Maria, no real suspects were identified.
More than 1,000 people came forward with information but police were no closer to finding the doorstep stalker and the case remained unsolved for decades.
In efforts to keep the investigation going, her heartbroken father, George Yianni, appealed to then prime minister Margaret Thatcher and the Commissioner of Scotland Yard.
He died in 1988 without seeing his daughter's killer brought to justice.
DNA evidence only came into use in the 1990s and in 1999, a scientist managed to extract an incomplete profile from semen on the bedspread where Yiannoulla was found which was later matched to a DNA sample from her body.
But a search of the DNA database produced no matches until last Christmas when police got Warnock's profile, the court heard.
At the time of the murder, 5ft 6in Warnock was aged 22 and gave the impression of being a "cocky ladies' man", with his hair carefully salon-styled and blow-dried like his Saturday Night Fever idol.
But when officers tracked him down, they found the balding defendant awaiting their arrival, quietly drinking beer in his underpants.
In a police interview he was asked what he looked like in the 1980s and he said: "How can I put it? Er, John Travolta?"
During the trial, Yiannoulla's brothers and sisters relived the nightmare of her violent death while her now 86-year-old mother was among those to give evidence.
The dignified family were even forced to listen as Warnock, formerly of Harrington Street in Camden, north-west London, maintained his claim that he used to go to their home to have sex with the popular and attractive young woman.
They wept and hung their heads as he told jurors of fictitious sexual encounters, saying: "It was always nice. It was not, you know, vigorous or anything. We didn't go mad. It was very quick. It was gentle."
Following the verdict, Detective Inspector Julie Willats said: "Immediately after the murder, there was a huge media impact on this. Lots of people came forward. Hundreds and hundreds of statements were taken over the years.
"I got a lucky break. It's the science that has solved this one for us."
From the moment Warnock had his DNA taken by police last year the clock began to tick, Ms Willats said: "He must have known we would be coming for him."
Investigators had searched in Cyprus and even as far afield as Australia while all the time, Warnock stayed in the local community.
Police began to think the killer was either dead or had moved abroad before Ms Willats received a text message during a trip to the theatre to tell her of the DNA breakthrough.
Not only did police match his DNA and fingerprints, the image produced from eyewitness descriptions of the suspect was "startlingly" similar to photographs of Warnock from the time.
He had never come to the attention of police before although in the absence of DNA testing pre the 1990s, it may never be known whether he was responsible for any other attacks, police said.