As police probe the suspect in Madeleine McCann’s case, other unsolved mysteries are being re-examined
It’s 8:00pm on a spring evening at the Ocean Club resort in Praia da Luz, a seaside holiday destination in Portugal’s southern Algarve region.
A mysterious phone call has just wrapped up, somewhere near the resort in the town of 3,500 people.
In a rented flat inside the Ocean Club, British doctors Kate and Gerry McCann have put their three children to bed.
The pair leave the patio doors unlocked, with the curtains closed, so that they can easily get back inside.
They’re preparing for one of their final meals with friends on a seven-night holiday in the area. often referred to as Little Britain, thanks to its popularity with UK tourists.
The McCanns would later tell police they were in the habit of taking turns checking on their children, 80 metres away from where they would routinely dine at a resort restaurant.
At 9:05pm on that night in May 2007, Gerry McCann checked in on his children. All three were sound asleep.
The 55 minutes which followed hold the key to what happened to a blonde-haired little girl who has since become a household name.
The couple’s three-year-old daughter, Madeleine, disappeared sometime between 9:05pm and 10:00pm.
Her siblings — two-year-old twins Sean and Amelie — were still in their beds when Kate McCann went to check on the children, but Madeleine was never seen again.
The breakthrough in the case came after more than a decade
In the 13 years since Madeline went missing, the case has become one of the most notorious missing persons investigations ever undertaken in Europe.
Even as the international hunt for Madeleine appeared futile, the case resonated with people around the world.
“There have been so many claims over the years that people had seen her,” forensic anthropologist and criminologist Xanthe Mallett said.
Despite extensive work by police in Britain, Portugal and Germany, and numerous appeals for information, there had never been a significant development.
After more than a decade of spurious leads and false alarms, in early June, German police made a major announcement on the McCann case: they had zeroed in on the likely culprit.
A 43-year-old convicted sex offender with an extensive criminal record, who they dubbed Christian B.
With a new lead, came more questions from the watching public.
Who was this man?
How had he evaded scrutiny for so long?
And did German police miss warnings about the potential suspect several years ago?
Police reveal Madeleine is likely dead
From the outset, Portuguese police investigating Madeleine’s disappearance were accused of incompetence.
They initially treated Kate and Gerry McCann as suspects, or “arguidos”, and admitted that vital forensic evidence might have been lost because the crime scene was not protected.
Dr Mallett, from the University of Newcastle, has followed the case closely for several years.
She says Portuguese police may have had “tunnel vision” on a theory that the McCanns were implicated.
She suggests that may have led to investigators failing to follow up on information which could have pointed to Christian B.
He was listed as a suspect all the way back in 2007 — but he was among hundreds considered.
“We know about the problems with the original investigative team and those leading it,” Dr Mallet said.
“Now you’re seeing the coalescence of police working together.”
Dr Mallett is now confident there will finally be a conviction.
“I think we can accept that they do have strong evidence that Madeleine is sadly dead,” she said.
Two months ago, German federal police and the Metropolitan Police in London appealed for information relating to Christian B.
They particularly wanted to know about an unknown person who spoke to him on the phone at 7:32pm on the night of May 3.
The call wrapped up at 8:02pm, as the McCanns were preparing to leave their apartment to join friends for dinner.
Police have received hundreds of tips from the public since June.
In a blunt statement, German police said they were now certain that Madeleine was dead, and that they were treating the case as a homicide investigation.
What do we know about Christian B?
Born in the German state of Bavaria, Christian B grew up in a children’s home.
In 1994, as a teenager, he was convicted of sexually abusing a child, but fled to Portugal to escape his sentence.
He was extradited to Germany to serve jail time in 1999.
He spent much of his twenties and thirties living a transient life, working odd jobs and running from police.
By 2007, he had returned to Portugal and was living in Praia da Luz when Madeleine disappeared — possibly in a VW campervan, which police have identified as crucial to their investigation.
German police say Christian B was a drug dealer who robbed a string of holiday homes in the area.
Last December, he was convicted of the brutal rape of a 72-year-old woman in Praia da Luz in 2005 — another case with a long history.
The 43-year-old is now in jail in Kiel, in northern Germany, convicted on drugs charges after again being extradited, this time from Italy.
This week, he lost his first appeal against the rape conviction — he’d argued the extradition was invalid.
Police say they lack a silver bullet to arrest him
Last week, German police spent two days searching a community garden near Hanover, where an old cellar and shack have since been destroyed.
Neighbours told the BBC that Christian B rented the plot not long after Madeleine was snatched.
Christian B has not been charged in connection with Madeleine’s disappearance, and German police have stressed that they lack further evidence.
German media reported Christian B’s lawyer as saying that his client “denied any involvement” in Madeleine’s abduction.
Lawyer Friedrich Fulscher said his client would not speak to police at this stage.
Prosecutor Hans Christian Wolters is certain someone in Europe knows more about his actions on that night in May 2007.
“Our investigation has turned up some evidence that was reason enough for us to go to the public,” he said.
Journalist Emmanuelle Chaze, who has been reporting on the case for Germany’s Deutsche Welle, believes German authorities will do whatever they can to keep Christian B behind bars.
But a final ruling in the appeal case against his rape conviction is still pending in the European Court of Justice.
“He’s already completed two-thirds of his [drug charges] sentence and he’s asking for early release,” she said.
“He presents a high risk to society.”
Solving the McCann case could have ramifications for other cold cases across Europe
The appeal for information regarding Christian B’s movements in 2007 could have major ramifications for other cold cases across Europe.
German police are also investigating whether he may be responsible for the disappearance of a five-year-old German girl, Inga Gehricke, in 2015.
She became known as the “German Maddie” when she vanished from woods in the town of Schoenebeck.
Could Christian B also be responsible for the disappearance of Rene Hasee?
The six-year-old was taken from a beach while on holiday with his family in Aljezur, in the Algarve, more than a decade before Madeleine disappeared in the same region.
Belgian police have also reopened an investigation into the murder of German teenager Carola Titze, who was found dead on a beach in 1996.
Her body had been mutilated and she was said to have been in contact with a German man in his twenties in the days before she was killed.
Irish woman Hazel Behan has also raised the possibility that it was Christian B who attacked her in her apartment in Portugal in 2004.
In that year, when she was working in Praia da Rocha, she was subjected to a horrifying ordeal when a stranger broke into her room and raped her repeatedly.
She told police the man was about 1.85 metres tall, had “blonde eyebrows” and spoke English with a German accent, but no-one was ever charged.
In June, she waived her right to anonymity to tell her story, saying she was sickened after hearing how similar her ordeal was to the rape of the 72-year-old American woman.
The ‘double-edged sword’ of the whole case
When Christian B’s name was linked to the McCann case earlier this year, there was a sense of horror in Germany, Chaze said.
Serious questions are now being asked of federal police after German magazine Der Spiegel reported that investigators were given new information about Christian B as far back as 2013.
“There’s been a lot of mistakes made,” Chaze said.
“He’d been out there on the loose … German investigators in 2013 invited him to come and talk to them as a witness in the case, but they gave out so much information that it gave him time to hide any incriminating [evidence].”
Dr Mallett believes the McCann case has been hindered by the global attention.
“It’s a double-edged sword for police,” she said.
“As with William Tyrell here, police constantly get tips, people wanting to help, providing information, and yet, police have to triage [those tips].
“They have to figure out which are the most likely to be of relevance, all the way down to the ones which are just totally random.
“But they have to research all of them. Any one of those could be a breakthrough.”
If this is the breakthrough the McCanns have longed for all these years, Kate and Gerry McCann say they hope it brings them peace, “whatever the outcome may be”.