One of the most famous missing persons cases in British history - the disappearance of three-year-old Madeleine McCann on holiday in 2007 - has been thrust back into the spotlight this week after police released information about a new suspect.
A German prisoner - previously convicted of sex offences against children - is now being investigated on suspicion of murder, the latest turn in a tragic case which has never been far from the headlines in Britain and further afield for 13 years.
And at the centre of the tragedy is a family that still has no answers about what happened to their little girl.
What happened 13 years ago?
In May 2007, Gerry and Kate McCann were staying in a holiday apartment in Praia da Luz, Portugal with their three children.
The couple went for dinner with a group of friends in a nearby restaurant, leaving their three children asleep in the apartment.
They checked on them throughout the evening but when Mrs McCann returned to the apartment at about 10pm, she discovered Madeleine was missing.
Her disappearance sparked a huge international search and sprawling investigation that continues to this day.
How the case touched hearts - and a nerve with some
The deeply-emotional story dominated British media for months with the little girl's face splashed on front pages and TV screens day after day.
Millions witnessed the anguish and despair felt by Mr and Mrs McCann as they issued desperate pleas for information and help.
The family's pain was only exacerbated when the couple also became targets of criticism - particularly in the tabloid press - for leaving their children alone while they went out with friends.
The trauma was heightened when Portuguese detectives questioned Mrs McCann after naming the husband and wife as suspects - an investigation only dropped in 2008, for lack of any evidence.
Later the McCanns' lawyer was to call their treatment by the British press a "national scandal".
The investigation's ups and downs
The investigation into Madeleine's disappearance has involved huge and costly police hunts across much of Europe. At times it was sustained by the McCanns themselves, using private detectives.
In Britain the most recent Metropolitan Police investigation, which began in 2011, has cost more than £11m.
Despite the identification of new suspects and persons of interest over the years, and fresh investigations of the crime scene - the mystery of Madeleine's disappearance remains unsolved.
The case has been the subject of multiple documentaries, including a 12-part Netflix series in 2019 that was criticised by Madeleine's parents.
What's happening now?
German police have just announced that a new suspect - a 43-year-old German man previously convicted of sex offences against children - is being investigated on suspicion of murder.
Currently serving a long prison sentence for sex crimes against young girls, "Christian B" travelled around Portugal in a camper van and was believed to have been in the area where Madeleine was last seen before she went missing.
British police still list the case as a "missing persons" investigation, and Kate and Gerry McCann say they have never given up hope. They described the latest lead as "significant".
"All we have ever wanted is to find her, uncover the truth and bring those responsible to justice," the couple said in a statement.