Gerry McCann has spoken in a personal video of his belief that his family was watched by "a predator" in the days before his daughter's disappearance.
In the video, filmed by a family friend in August and to be screened on BBC One's Panorama, he tells of a "window of opportunity" taken by an abductor.
That belief made him and wife Kate "sick to the core", he said.
Madeleine, of Rothley, Leics, vanished from a holiday apartment in Portugal on 3 May, days before her fourth birthday.
The footage - filmed in Portugal by friend Jon Corner and to be shown as part of a Panorama programme on Monday - captures a time when suspicion over the disappearance began to fall on the couple.
The McCanns, both 39, became suspects with "arguido" status in the case in September but deny any involvement.
Mr McCann said that, before Madeleine went missing, he and his wife had been concerned by the security at the back of their Praia da Luz apartment when "maybe the weak spots were at the front".
"It's a corner flat with trees overlooking it - somebody could be hiding there or watching out of view," he said.
He added: "I've no doubt that Madeleine was targeted and that makes us sick to the core to think that someone was watching us and our daughter and then targeted her - I think the true word is a predator.
"But you just don't think there's any trouble and it's certainly the furthest thing from our mind."
Campaign pressure
In one scene on the video, Kate is shown hanging washing out to dry while, in another, Mr McCann is shown making missing posters of Madeleine on his laptop computer.
Also in the film, Mrs McCann talks of the pressures posed by the campaign to find Madeleine and her regret at leaving their children alone in the apartment on 3 May.
The couple dined with a group of friends as they left Madeleine and their two other children asleep in an apartment nearby.
"There's not a textbook about it is there? Like what to do when your daughter gets abducted," she said.
"It's awful and horrible for anyone to have to go through and we are just doing what we think is best."
Possible sighting
The Panorama programme also features an interview with the McCanns' friend Jane Tanner, who dined with the couple in a tapas restaurant on the night of Madeleine's disappearance.
In an exclusive interview, she told the BBC she saw a man carrying a child through Praia da Luz.
Meanwhile, the head of the Spanish private detective agency hired by the McCanns has told US network CBS in an interview he was certain Madeleine was abducted and the abductor was close to being caught.
The couple's spokesman Clarence Mitchell has also confirmed that a possible sighting of Madeleine somewhere in Portugal on 5 May was now being investigated by private detectives.
Panorama: The Mystery of Madeleine McCann will be shown on BBC One at 2100 GMT on Monday, 19 November.