It's an extraordinary proposition: that the U.S. Central Intelligence Service created the AIDS virus decades ago in its political battle with Cuba. What's more, that former U.S. president Barack Obama only moved to further lift the embargo on the tiny nation in 2016, to get access to a vaccine the country had created.

To most, the notion is easily dismissed.

But, wrap it in the packaging of a slickly produced video with emotive pictures and an authoritative voice doing the narration, and the conspiracy theory quickly becomes convincing.

"That's the true reason for the financial and health embargo against the island that has lasted 50 years," the voice on the video says.

"The idea is to create a shock reaction," says Thomas Huchon, one of a group of French journalists who created the video to illustrate how easily fake news can be believed.

WATCH: Is this documentary trailer real or fake news? French journalists shot a slick conspiracy theory-laden film to to teach students how to identify fake news. 1:05

Huchon works for online documentary site Spicee.com. He and his colleagues have now shown the video to students in more than 80 schools in France. The teens watch the video and discuss the consequences of the shocking content until Huchon reveals that it's all fake.

'They have been duped...but with a purpose'

"Well, they're a little bit mad. And, that's normal because they have been duped. They have been tricked. But with a purpose," he says.

The purpose is to expose them to fake news, and then to develop with them, as Huchon calls it, "a few reflexes … to fact-check information."

Watch the full interview with Thomas Huchon on The Investigators, Saturday at 9:30 p.m. ET and Sunday at 5:30 p.m. ET on CBC News Network.

Those reflexes include learning to look for the author's name and searching out other work the author has written to see if they truly exist, or checking the publication to see what its credentials are. He suggests the same fact-check technique for videos and pictures, saying if there's no accompanying photographer's credit, it can often signal a picture that's been Photoshopped.

Challenging notions of fake news

Huchon is an investigative journalist who says he became concerned about fake news in the aftermath of the Paris bombings in 2015 that killed 137 people. He says the conspiracy theories that flooded the internet were convincingly presented with high production values, that suggested to viewers that they could only have come from legitimate news agencies.

'I think over the last 10 years the professional news broadcaster [and] the professional journalist has lost ground on the internet,' Huchon said. (Twitter) "There has been a professionalization of the work that has been done on the internet about fake news," he says. "I think over the last 10 years the professional news broadcaster [and] the professional journalist has lost ground on the internet."

He believes many people mistakenly believe that fake news will be easier to spot because it's poorly written, with obvious spelling or grammatical errors, a nod to fake news created in other countries and roughly translated to English.

But Huchon says that notion needs to be challenged.

"I think that most of the people see this as something they would never fall into and that's where the problem starts. It's when you think that you are protected that you are going to fall into the trap of fake news."

Thomas Huchon spoke to CBC News for this week's episode of The Investigators with Diana Swain.

Also this week on The Investigators with Diana Swain: Washington Post reporter Mary Jordan talks about the challenge of covering U.S. first lady Melania Trump. And CBC News producer Chelsea Gomez talks about the story of an Ontario's man's battle for workplace compensation after developing a terminal illness.