The parents of missing Madeleine McCann have said they are "greatly encouraged" by new information about their daughter's disappearance.
A reconstruction of the "latest, most detailed understanding" of the events around the time she went missing will be shown on BBC Crimewatch on Monday October 14.
It comes after the Metropolitan Police revealed a vast log of mobile phone traffic could be the key to finding out what happened to the-then three-year-old.
Scotland Yard detectives, who have interviewed 442 people as part of their review-turned-investigation into Madeleine's disappearance, hope to track down as many people present in Praia da Luz, Portugal, on or around May 3 2007 as possible.
Madeleine's parents, Kate and Gerry McCann, said: "We are greatly encouraged by new information coming to light with pieces of the jigsaw now fitting together. We are really hopeful that the forthcoming appeal on Crimewatch will bring further new evidence which will take us a step closer to finding Madeleine and to bringing those responsible for her abduction to justice."
A three-year-old actress is to play Madeleine in the Crimewatch reconstruction, as a small production team from the programme spent a week filming abroad for the new appeal.
Detective Chief Inspector Andy Redwood, the senior investigating officer, said: "We now believe we have the most complete picture to date of the events surrounding her disappearance.
"We are now making targeted and new appeals for help from the public. I truly believe there are people out there who hold the key to Madeleine's disappearance, and that so far they may be completely unaware of that fact."
Crimewatch presenter Kirsty Young speaks to the McCanns in the new programme, while presenter Matthew Amroliwala has been to Praia da Luz to explore the new focus of the police investigation.
The McCanns and Mr Redwood will also be speaking to Kirsty live in the studio.
Crimewatch editor Joe Mather said: "We've been working very closely with the Metropolitan Police on a new Madeleine McCann appeal for several months.
"We're very hopeful that this major reconstruction along with the substantial new lines of enquiry will prompt viewers with vital information to get in touch with the officers in studio on the night of the programme."
Earlier this week, Scotland Yard revealed that since launching its own investigation, 41 people of interest have been identified, including 15 UK nationals, up from 38 people of interest including 12 UK nationals established in July.
Detectives have issued 31 international letters of request (ILOR) to mostly European countries in relation to some of the persons of interest as well as accessing phone records.
A large but "manageable" list of phone numbers identified as being present in Praia da Luz - though not necessarily used to make phone calls - has been drawn up by detectives with a "significant" number unattributed to any named person.
And significantly, police officers are now able to create a log showing calls being made at the time of Madeleine's disappearance.
The latest appeal will also be broadcast in Holland and Germany.
Madeleine went missing from a holiday apartment as her parents dined at a nearby tapas restaurant with friends.
The Portuguese investigation officially closed but authorities there are backing the Scotland Yard inquiry and officers from both countries will work together in pursuing new leads.
The Metropolitan Police now has a team of six Portuguese detectives based in Faro, who are carrying out inquiries on its behalf.
The McCanns are currently suing former police chief Goncalo Amaral for libel over claims in the book The Truth Of The Lie.
Read more on Madeleine McCann.