The final stretch of the road where Diana Quer was last seen.

Although the last time anyone saw her alive was 2.40am, her white iPhone 6 continued to send out signals until approximately 5am, indicating a fast eastward journey toward an area known as Taragoña, in the nearby municipality of Rianxo, on the Arousa estuary. That is where the phone was eventually found, lying in the mud, by a local shellfish harvester.

Following the young woman’s disappearance, a massive search operation was deployed. Scores of volunteers combed the nearby countryside for days on end. Some of the world’s best scent dogs were brought in from Madrid to sniff out any possible traces of blood or bodily fluids. Human and animal trackers ventured into old sawmills and abandoned factories in search of clues. Ships scoured the coastline, and helicopters scrutinized the woods from above.

In December, a support group received an email purporting to come from Diana Quer

Meanwhile, in a major technological effort, Civil Guard officers examined millions of telephone signals and finally honed in on 80 phone users whose own signals followed the same pattern as Diana Quer’s phone between 3am and 5am that night.

They also reviewed footage from around 40 surveillance cameras and checked thousands of license plates. They interviewed friends, relatives and anyone else with the slightest connection to Diana, both in Galicia and in her permanent residence of Pozuelo, an upscale suburb of Madrid.

Witnesses stepped up for the first two months to report Diana sightings, to testify to the family fights they had seen and heard, and to explain what the victim had been wearing on the night of her disappearance – her clothes were alternately described as pink shorts or long dark pants, depending on the witness.

Some individuals describing themselves as fishermen asserted that Diana showed up at the solitary dock of Taragoña inside a car with several men, then got into a second vehicle after having an argument with the first driver. This seemed like a solid clue until the sources were later described by the Civil Guard as unreliable.

Now, investigators are once again poring over the 200 or so testimonies sitting on their desks. At this point, they think it is unlikely that Diana reached Rianxo alive, and they suspect that her attacker may have dropped the phone there on purpose as a distraction.

The inquiry remains open under a new investigating judge who is keeping the proceedings under seal. And authorities continue to hold that “all hypotheses remain open.”

In fact, the kidnapping option is under consideration again, even though it was initially discarded by the Civil Guard, who favored the idea that Diana left of her own free will after a fight with her mother and sister.

The Civil Guard believes that all the media attention may have worked against the search for Diana

Diana’s complicated family life continued to make headlines weeks after her disappearance, with both her parents, who are separated, sending out conflicting versions about life at home.

The Civil Guard believes that all the media attention may have worked against the search for Diana. Television coverage of the case achieved high ratings, especially after her parents had a live confrontation on set. In an added twist to the tale of woe within a well-off suburban family, the mother lost custody of the younger daughter, Valeria.

In December, a support group for families of missing persons called SOS Desaparecidos received an email purporting to come from Diana Quer. Investigators quickly concluded that somebody was attempting to pass themselves off as the young woman, and noted that great care had been taken to avoid being traced – a fact that suggested it was more than just a joke in bad taste.

The email linked to a tweet by the real Diana Quer, who wrote over a year ago “how good it would feel to disappear for a little while.” The association filed a complaint in court, asking for an investigation, but it has yet to receive a reply.

Sources at the Civil Guard admit that the investigation is stuck. Officers are now waiting to see if some new clue turns up, or if one of the suspects on their shortlist – some of whom have ties to the drug world in the Arousa estuary – makes a mistake.

In the meantime, Diana’s family has hired a team of private investigators. But six months later, the case seems nowhere closer to being solved.