People can't stop watching this video of Bill Hader morphing into Tom Cruise.

Have you ever seen Bill Hader’s impersonation of Tom Cruise?

It’s… flawless.

So flawless, in fact, that you might not have noticed that Bill Hader actually morphed into Tom Cruise while speaking to David Letterman on his late night show.

In a new YouTube clip, which has since been viewed over three million times, Hader is sharing a story about his encounters with actors Tom Cruise and Seth Rogen, when those actors’ faces seamlessly – and terrifyingly – morph into his own.

Confused? We don’t blame you.

Watch a clip from Bill Hader’s interview with David Letterman below. Post continues after video.

The newly edited clip of the Saturday Night Live comedian is actually an example of an expertly crafted deepfake video.

But what exactly is a deepfake, and should we be… concerned?

Here’s everything you need to know.

What is a deepfake?

Put simply, a deepfake is an AI-generated edited video that shows someone doing or saying something… that never happened.

Think fake images created on Photoshop – but the video and audio equivalent.

While the most convincing deepfakes are generated by powerful computers and intelligent software, it’s not just Hollywood heavyweights using the technology.

After all, anyone can use online software or even intelligent apps, like FakeApp, to create convincing deepfake videos.

To create a deepfake, the technology can make facial models using just one single image. However, with more high quality images and video footage, the AI has the power to create an entirely believable, realistic deepfake.

Because of this, celebrities and politicians, like US President Donald Trump, are easy targets.

How are deepfakes used?

The term ‘deepfake’ first emerged on Reddit, when users began producing fake pornographic videos of female celebrities.

A number of celebrities, including Ariana Grande, Gal Gadot, Emma Watson and Selena Gomez, were routinely targeted in the videos, as their faces were inserted into fake adult videos by swapping the actresses’ faces with adult film stars.

The technology has also been used for entertainment purposes.

In 2016 film Rogue One: A Star Wars Story, face-swapping was used to create a younger Princess Leia in the film, by superimposing models of the original actor’s faces onto stand-in actors.

It was also famously used in Fast & Furious 7, when the late Paul Walker’s face was superimposed onto his brothers Cody and Caleb after he passed away before filming was completed.

YouTube channel ‘Ctrl Shift Face’, who created the Bill Hader deep fake, have also created a number of videos, including numerous clips from The Shining, where Jim Carrey’s face is melded with Jack Nicholson’s face, and another clip of Bill Hader impersonating (and, becoming) Arnold Schwarzenegger.

Speaking to The Guardian, however, the man behind the YouTube account claimed that he doesn’t want to mislead any of his viewers.

“I always mention that it’s a deepfake in the title and description,” he said.

“It’s an arms race: someone is creating deepfakes, someone else is working on other technologies that can detect deepfakes. I don’t really see it as the end of the world like most people do.”

Should we be worried about deepfakes?

Although deepfakes can be used for entertainment purposes, they also have the potential to be nefarious.

For example, a deepfake video could potentially have the power to sway an entire election.

In the US currently, a video of Democratic politician Nancy Pelossi, which was purposefully slowed down to make her appear drunk, has already conned thousands of viewers, meaning we’re not far away from seeing the impact of deepfake videos on politics.

Similarly, in 2018, Buzzfeed Video created a clip in which former President Barack Obama appeared to call Trump “a complete and utter dipsh*t”. In reality, however, Obama was simply a deepfake, and his words were voiced by Jordan Peele.

It’s essentially fake news – but even more convincing.

In a recent interview, Hany Farid, Professor of Computer Science at Dartmouth College, explained just how much deepfake videos could potentially affect the world.

“Imagine this scenario – a video is produced of Donald Trump saying, ‘I have just launched nuclear weapons against North Korea,'” Faird explained.

“That video goes onto Twitter and goes viral in 60 seconds. A minute later, North Korea responds [with a nuclear weapon].”

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