‘John Travolta’ killer busted after 34 years

Her attacker forced his way in and up these stairs

Police had in mind an idea of what had happened to 17-year-old Yiannoulla Yianni the day she was murdered, 13 August 1982. Yianni had returned home from working in her family’s shoe-repair shop in north London and begun to prepare the evening meal for her family, a leg of lamb. She was listening to music when she heard a knock at the door. Why she answered the door was unknown, but once inside, her attacker chased her up the stairs, grabbing her ankle as she tried to flee. Pieces of a broken chain were found on the carpet. Once up the stairs, she had attempted to hide in her brother’s bedroom, the only room in the house with a lock, but the attacker had kicked down the door, taking it off its hinges. More pieces of Yianni’s jewellery were found upstairs, her golden bangle and the fragments of a broken ring left behind as she struggled to get away from the man who would kill her moments later.

Fleeing room to room, she was eventually cornered in the bathroom, and while she hid in the bath, her attacker burst in and ran the bath taps, soaking her in the process. This would later explain her wet appearance when her body was found. Her parents returned to their house just before 3pm to find their daughter’s body on their bed.

Yiannoulla’s broken ankle chain was found at the scene of the crime

Yianni was an aspiring beautician who loved to spend her time styling her hair and sitting under a hooded hairdryer in her Hampstead home. Her family often called her Lucy after the actress Lucille Ball because of her bubbly personality. She had just completed her O-levels and was awaiting the results, which would hopefully bring her one step closer to her dreams. But those dreams and the hopes her family had for their daughter were dashed when her body was discovered as they returned home from work. Her skirt had been pushed up and her top and bra had been slashed open, exposing her further. She had been bitten and punched.

The post-mortem examination revealed that Yianni had died from suffocation; police suspected her attacker had placed her in a head lock. It was also discovered that the innocent young woman, a virgin before her merciless attack, had been raped.

In the early 1980s, technology to test DNA evidence was not available. Instead, a televised reconstruction of what had happened to Yianni was broadcast on appeals show Police 5 in the hope it would encourage witnesses to come forward and shed some light on the case. Based on testimony from witnesses who had seen Yianni laughing on her doorstep with a man shortly before her death at around 2pm, detectives had an idea of what the killer looked like: they believed him to be in his 20s, with black, neatly combed hair. He had been wearing a blue denim jacket at the time of the murder and was approximately 1.7 metres tall.

Scotland Yard launched a major investigation to find Yianni’s killer. More than 1,000 potential suspects were interviewed while hundreds of male pupils and staff at Yianni’s school were asked to give fingerprints.The schoolgirl’s father died of a brain tumour in 1988, never knowing who had killed his daughter. Repeated appeals were made for more information about Yianni’s death and though the trail went cold, detectives routinely reviewed the case. A police enquiry into Yianni’s death showed that up to three months before the murder, the victim, her sister and mother had reported being followed twice by a man with a Mediterranean complexion and black, combed-back hair near their home.

In 1999, advances in DNA techniques allowed a semen sample that had been recovered from near the victim’s body to be examined, but it gave no indication as to who the killer could have been. In 2003, a £10,000 reward was offered for information leading to a conviction and 5,000 appeal leaflets were posted through doors in the area.

As further advances in DNA technology were made, analysis of the stain on the bed sheet provided the police with a near-complete profile. Much to the frustration of all involved, when it was put through the UK criminal database in the hoped of finding a match, there was none. Further testing was also conducted on fingerprints and palm prints that had been recovered from the edge of the bath at the crime scene, but this provided no immediate clues.

Police pieced together evidence gathered from the scene, but were unable to find a match in the national DNA database

In December 2015, police arrested 56-year-old James Warnock for possessing indecent images of children. As a matter of routine, he was told to give a DNA sample that would then be put on the national database. When it was added, a match appeared for the DNA that had been extracted from the semen stain found in the Yianni home 33 years previously. Police said that the chances of it matching anyone else were one in a billion.

During an interview with Warnock, police asked him what he had looked like during the 1980s. He replied: “How can I put it? Er, John Travolta?” Warnock was charged with killing Yiannoulla Yianni in January 2016. Detective Inspector Julie Willats, who became the senior investigating officer on the case three years previously, said: “He came across as a bit of a Jack-the-lad and a very confident liar. His body language was telling – he got fidgety when asked for details of his sexual relations with Yiannoulla.”


Although Warnock did not deny he knew Yianni in his police interview, he denied having known she had been killed or seeing it in the local paper


It came to light that the 22-year-old Warnock had been living near to the house in which Yianni was killed in 1982. He denied the allegations of rape and murder and attempted to explain the evidence against him by saying that he and Yianni had been seeing each other in secret, but his claims were heavily rebuffed. The prosecution argued that Warnock had noticed the victim and had probably been the man following her in the streets in the months before her murder. Having seen her return that fateful day, he decided to strike while she was alone.


In July 2016, Warnock was sentenced to life in prison and ordered to serve a minimum of 25 years for the rape and murder of Yianni, as well as a further six counts of distributing indecent images of minors during 2013 and 2015. While sentencing Warnock at the Old Bailey, Judge Nicholas Hilliard, the recorder of London, told him that he would most likely die in prison and said it was, “…impossible to understand how one human being could do this to another”.

This article featured in issue 15, which can be bought here. Want to read more nail-biting breakthroughs? Subscribe to the magazine and save up to 25% off the cover price.