British detectives investigating the 2007 disappearance of Madeleine McCann in Portugal will on Monday publish new e-fits of men they want to contact, in a major public appeal.
The primetime television program will also present a fresh timeline of events surrounding the disappearance of the British girl from her family's holiday apartment, just a few days before her fourth birthday.
It will include a new 25-minute reconstruction as well as live interviews with Gerry and Kate McCann, who launched a global media campaign to find their daughter and still hold out hope she is alive.
Portuguese authorities closed their investigation in 2008, but London's Metropolitan Police spent two years reviewing the evidence and opened their own probe in July this year.
Last week, the British force said analysis of mobile phone data from thousands of people who were in the resort of Praia da Luz when Madeleine disappeared could provide a new lead.
The detectives have interviewed 442 people over the last couple of years and have identified 41 potential suspects, although no arrests have been made.
In the BBC Crimewatch program on Monday night, e-fits of men seen in and around Praia da Luz at the time will be published in a bid to identify the men and eliminate innocent sightings.
"Primarily what we sought to do from the beginning is try and draw everything back to zero,'' said the chief investigating officer, Detective Chief Inspector Andy Redwood, in a clip from the program released to the media.
"Try and take everything back to the beginning and re-analyse and reassess everything, accepting nothing.''
He said detectives were focused on the time between 8:30pm on May 3, 2007, when Kate and Gerry McCann left the apartment to dine at a nearby tapas restaurant with friends, to when Kate McCann found Madeleine was missing at 10pm.
"Our work to date has significantly changed the timeline and the accepted version of events that has been in the public domain to date,'' Redwood added.
The appeal will be shown in Germany and the Netherlands after Monday's British broadcast, in a bid to widen the search for new information.
Last week the McCanns said they were "greatly encouraged by new information coming to light'' and said they hoped the BBC appeal would take them closer to find Madeleine.