Reporter: Richard Bilton, BBC Panorama
Producer: Michael Chrisman
Just what did happen to English toddler Madeleine McCann? It's one of the most bizarre and intriguing mysteries of recent times.
And one with striking parallels to our own Azaria Chamberlain case.
Did Madeleine McCann's parents really kill her as they holidayed at a Portuguese resort? Or was she kidnapped by a sexual predator, as Kate and Gerry McCann claim?
It's a question that has sparked months of frenzied speculation. But despite all the intense media pressure, all the whispering, Kate and Gerry McCann have remained resolute �?they had nothing to do with Madeleine's death, they even believe she may be alive.
Yet six months on, they're still the prime suspects.
On Sunday night, for the first time, you'll hear them talk openly about their daughter's disappearance, hear their version of events on that tragic night in May.
And you can be the judge.
Transcript
RICHARD BILTON: From anguish ...
KATE McCANN: Please continue to pray for Madeleine �?she's lovely.
RICHARD BILTON: �?to a form of celebrity.
GERRY McCANN: This poster is the one that we did in conjunction with JK Rowling for the distribution.
RICHARD BILTON: Then doubts ...
REPORTER: Kate, Kate, are you ...?
RICHARD BILTON: �?and finally suspects.
LAWYER: They have both been today declared arguendo.
RICHARD BILTON: Their story has been the same from day one �?their daughter was abducted.
GERRY McCANN: We have played no part in the disappearance of our lovely daughter, Madeleine.
KATE McCANN: It's awful and horrible for anyone to have to go through. And we are just doing what we think is best and we don't know �?we don't know if what we are doing is right, you know?
RICHARD BILTON: April of this year, the McCanns, along with a group of friends �?who all have pre-school children �?decide to go for an early break in the sun. They come here �?to the Ocean Club in Praia da Luz, Portuguese Algarve.
KATE McCANN: It was funny, we were having such a good time and it was like we were with our friends and their kids and because there was a group of us you're just, you're into each other, do you know what I mean?
RICHARD BILTON: The week-long holiday is coming to a close. Day six is Thursday May 3. We've produced this model of the Ocean Club to clearly show the key areas, and where people were. The tennis courts and pool area, the tapas bar and here, apartment 5a where by 5.30 in the evening, the McCanns say the children have been picked up from their kids clubs, and they're all back together. Gerry McCann says he reads the children a story and all three are asleep by 7.30. The couple say they have a glass of wine before, at 8.30, they leave for the tapas restaurant. It's on the complex �?about 70m away. They'd eaten here every night of their holiday, with their friends.
GERRY McCANN: One couple we'd played tennis with, and we chatted to them, and, er, and then some of our friends started arriving and they left shortly after that. And I think at that point we might have been the only table.
RICHARD BILTON: There's a party of nine and most people are drinking. All the couples have children in the apartments. They say they took turns to check up on them.
KATE McCANN: We all knew what we had to do �?what we were doing. You know, it worked as a system we had going and it just seemed totally right, you know.
RICHARD BILTON: Gerry McCann says he went at just after 9.00 to check on his children. He remembers looking down at Madeleine. He spent a moment thinking how beautiful she looked and how lucky he was. He says this was the last time he saw his daughter. Now what follows is a crucial part of this story. The police say that there are many inconsistencies in what the group who were having dinner with the McCanns �?the so-called Tapas 9 �?have said in their witness statements. Jane Tanner is the only one of the group of friends who has agreed to speak to us. Why have you chosen to speak now?
JANE TANNER: Because we were ... Well, I've not spoken because the Portuguese police told us not to talk about the case at all. I think, maybe I'm talking now because I'm being called a liar and fantasist and all this and I know what I saw and I think it's important that people know what I saw because, you know, I believe Madeleine was abducted.
RICHARD BILTON: Jane Tanner thinks about checking on her children.
JANE TANNER: At the top of the road, I just saw somebody walking across the top of the road so I was reasonable distance away from them. And that person was carrying a child.
RICHARD BILTON: And you say a person �?a male or female?
JANE TANNER: Oh, a male, a male.
RICHARD BILTON: Describe exactly what he's carrying, what you can see?
JANE TANNER: Well, I can just see, I could tell it was a child and I could see the feet �?and sort of the feet and the bottom of the pyjamas.
RICHARD BILTON: From your sketch, he appears to be carrying a child in a sort of unusual way?
JANE TANNER: Yes, he was carrying sort of across the body like that. In retrospect, you would probably think somebody would carry them more against the shoulder.
RICHARD BILTON: At about 10.00, it's Kate McCann's turn to check on the children. Madeleine is missing. Kate McCann says she searches the flat three times before raising the alarm.
JANE TANNER: And then I saw Kate running around shouting Madeleine, and Kate said to me, 'Jane, Madeleine's gone, Madeleine's gone'. And that's the first that I heard. Suddenly Madeleine's not there, and I've seen somebody that, then you think, 'Oh, that maybe was a bit odd'. It just seems too much of a coincidence.
RICHARD BILTON: The police say the first call they receive was at 10.40. By dawn, a major search of the whole resort is under way.
GERRY McCANN: We would again like to appeal for any information, however small, that may lead to the safe return of Madeleine.
RICHARD BILTON: The first appeals are made �?but what we didn't know at the time, was that some Portuguese detectives are already telling Portuguese journalists that they don't believe the McCann's story. Within days, Kate and Gerry McCann found themselves being judged by the media.
KATE McCANN: Madeleine is a beautiful, bright funny and caring little girl. She is so special. Please, please do not hurt her. Please don't scare her. Please tell us where to find her.
RICHARD BILTON: It was reported that police suspicions were fuelled by the couple's behaviour, that in these early appearances, Kate McCann seemed too cold, too controlled.
KATE McCANN: We need our Madeleine. Sean and Amelie need Madeleine, and Madeleine needs us.
RICHARD BILTON: And it's in this atmosphere that a former detective goes on Portuguese television and, without any corroboration, accuses the McCanns of being swingers. The Portuguese police publicly disowned the allegation, also denied by the McCanns, but such stories are damaging.
REPORTER: How do you deal with the fact that more and more people seem to be pointing the finger at you saying the way you behave is not the way people would normally behave if their child is abducted and they seem to imply that you may have something to do with it?
KATE McCANN: To be honest, I don't actually think that is the case. I think that is a very small minority of people that are criticising us. You know, we are very responsible parents and we love our children so much, and I think it's only a very few people that are actually criticising us.
RICHARD BILTON: That question seemed extreme at the time but there was more and more focus on Kate and Gerry McCann. But one film crew was welcome. Jon Corner is a film producer. He's also godfather to the McCann twins.
JON CORNER: You can see the twins are just playing, you know, and you can see it's a normal house, You've got toys and stuff on the floor.
RICHARD BILTON: So far this footage has remained private. This is the first time it's been seen.
JON CORNER: What's quite poignant about it is you see a father sitting on his own, in his bedroom, in a foreign country, desperately looking for his daughter and seeing that quite upset me.
GERRY McCANN: When you see videos or the pictures I haven't seen for a while, the common ones, I think, I've become a bit desensitised to, but the ones, the ones that haven't been used as much are much more difficult to look at, and particularly video.
KATE McCANN: You think to yourself, 'How does anyone cope with that? How could you get through another day?' And then you throw it back to yourself and think, 'How did I get up this morning? How did I get a shower, how did I get my breakfast?' And something obviously gets you through it apart from the first few days, which you have total, sort of, physical shutdown. But something gets you through it.
JON CORNER: I said to them that I think there's a possibility that Madeleine may not be the story eventually, that you may be the story.
RICHARD BILTON: What did they say?
JON CORNER: They were quite distressed by that, really.
RICHARD BILTON: He was right to sense a change. Forensic teams had found what they thought to be specks of blood in the McCann apartment. Sniffer dogs had reportedly reacted to the scent of death in the McCann hire car and on Kate McCann's clothing. People were starting to think what had previously seemed unthinkable.
RICHARD BILTON: Part of this inquiry is now shifting from a possible abduction to investigation that might involve death or murder. Were you aware of those sorts of shifts?
GERRY McCANN: We're not naive, but on numerous occasions the Portuguese police have assured us that they were looking for Madeleine alive not, you know, Madeleine being murdered, and I don't know of any information that has changed that.
RICHARD BILTON: And by now, the forensic work is shaping the case. The police doubts are more serious. On Thursday, 6 September, Kate McCann is dropped off in Portimao. She's been called in for questioning. She finally gets out at 1.00 in the morning. At 3.00 in the morning, after Kate McCann has returned to her villa, her lawyer arrives with what seems to be a deal �?plead guilty to manslaughter and escape with only two years in jail. This was a turning point. First, they're named as official suspects.
LAWYER: Kate and Gerry McCann �?they have both been, today, declared arguendo with no bail conditions.
RICHARD BILTON: Then, they decide the time has come to leave Praia da Luz, to go home without Madeleine. So what exactly is the case against the McCanns. Some of it is tenuous, to put it mildly, and hard to disentangle from wild press speculation. It was widely reported, for example, that the body was shifted in the back of this vehicle, a Renault Scenic the McCanns hired 25 days after Madeleine disappeared. We understand DNA evidence has been recovered from the underside of the carpet lining in the boot of that Scenic. Fluid and hair from a corpse, not necessarily human and a separate DNA sample that's a partial match from Madeleine and comes from a primary source. Our senior Portuguese contact has said the partial results that have been sent are inconclusive, and that he doesn't expect the full set will ever be enough �?on its own �?to bring a case.
CARLOS ANJOS: TRANSLATION What did come to Portugal were not conclusive results, but rather said to be indicative.
RICHARD BILTON: It's a case that divides people. Those who think that somehow the McCanns are involved and those who don't.
GERRY McCANN: I've no doubt that Madeleine was targeted, and that makes us, you know, sick to the core to think that somebody was watching us and our daughter and then targeted her and, er, and I think the true word is, er, you know, a predator.
KATE McCANN: They've been watching us over a matter of days, I'm sure. You know, they know, they must have known, you know, that Gerry must have been into the apartment, and then �?you're right, there's only a small window of opportunity, but you know.
RICHARD BILTON: Painfully for some, the more the couple disclose about how insecure the flat was the less wise their decision appears to leave the children unattended.
GERRY McCANN: Clearly at the time, we felt what we were doing was quite responsible. If we were going to be dining further away or around the corner we would never have left the kids. And with hindsight �?everything with hindsight �?it's all taken in the context of your child being abducted, and if we could turn back the clock and that would be, you know, and we'd just rewind as fast as we could.
KATE McCANN: There isn't a day that goes by that I'm not kind of thinking, 'Why did I think that was okay?' You know, 'Was I wrong in thinking that was okay?' You know, all I can say to myself is I know how much I love my children. I know I am a responsible parent and I know that, you know, and I've just got to keep saying that to myself really.
RICHARD BILTON: More than six months on, there's still only one real fact, and that is Madeleine McCann disappeared on the night of May 3, 2007 and has not been seen since. Now potentially, the month ahead is crucial �?barring any other developments, the forensic evidence may force the police here in Portugal to decide once and for all if the McCanns are to face any charges. If they do, then they'll have the chance to clear their name. If they don't, then Kate and Gerry McCann could face the rest of their life without their daughter, but with the suspicion that they were involved in her disappearance.
KATE McCANN: It's not about us �?we were bobbing back and forwards several times an hour to see the kids, so, you know, it's not about us. You know, I think the problem is it's this predator, basically, who's been watching us which gives you the shivers anyway. They've broken into the apartment and taken Madeleine out of her bed.