Josh Hartnett on The Fear Index: "This is one of the most difficult jobs I've ever taken on"

It didn't make the critical splash achieved by the original, but it was a springboard for Hartnett, who went on to enjoy a career spanning romantic comedies, war epics, horror, sci-fi and just about every genre going.

He's predominantly associated with the big screen, but there have been a handful of TV projects that have caught his eye, such as his most recent work, The Fear Index, which premieres today on Sky Atlantic.

The psychological thriller is comprised of just four parts – a delicious offering in a world teeming with series that rumble on for double that, and longer. But that won't come as a surprise to those who have read the Robert Harris book on which it's based, which unfolds over just 24 hours.

Hartnett leads the cast as Dr Alex Hoffman, a “prodigy” who was previously flexing his intellectual muscles at CERN, the world-class scientific research facility, before going on to form his own investment company with his close friend Hugo (Arsher Ali).

"They took out some of the more internal and character driven elements," said Hartnett of the contrast between the series and the original source material. "And I think that's necessary for something like this. For a four-hour series, you want people to be wanting more, continually watching and continually on the edge of their seats."

But the book remained a vital tool for Hartnett, enabling him to fully enter Alex's inner landscape. "It's nice to have that cheat code, as it were," he added.

From the outside looking in, Hoffman Investment Technologies appears like any other establishment of its kind. But Alex and Hugo have a secret weapon fuelling their success: VIXAL-4 , an AI system developed by Alex that feeds off global events, from elections to terrorism to disease outbreak, to dominate the stock markets. It's an approach referred to as the volatility index, or fear index by traders.

"The more money it makes, the more access it has, the more it's learning," said Hartnett. "But Alex is not really into it for the money, even though he's having this enormous influence on the events around him, political and human."

Hugo, by contrast, is motivated entirely by the fiscal gains, which leaves you questioning just how nourishing their brotherhood is.

The capability of Alex's apparatus is most apparent following a plane crash in the second episode, from which the company is set to benefit substantially. But while monitoring global affairs and making data-led decisions is one thing, seemingly knowing exactly what disasters will occur and when is another matter entirely.

How has VIXAL acquired that level of knowledge? Has Alex lost control of his creation, or is it merely following his orders?

"It's a story about unchecked power and how dangerous that can be," said Hartnett, describing Harris's work as applying the analogy of Frankenstein “to the modern world”.

“It’s beautiful," he said. "It felt so natural. I was wondering why no one had done it before, Frankenstein's monster as AI. It's just so elegant.

Fear feels like an especially timely theme to unpack given the sheer number of unsettling and destabilising events that we're exposed to on a near-constant loop. From the impact of the pandemic to the resurgence of the far right, the climate change crisis to the rumblings of nuclear war, it's incredible that any of us manage to climb out of bed in the morning. We are, in many ways, teetering on a knife edge.

But as Hartnett notes, "that isn't unique to us in this time".

"Yes, this fits into our modern world and that sense of impending doom that we all seem to have right now, but I think every generation has that moment where they think that they're at the very end of the world," he said. "I think it says something about us that we always think that we're the last generation."

He went on to cite the Vietnam and Cold Wars, US presidential assassinations and the attacks on civil rights activists.

"We're always dealing with something as a human race that seems to be close to the annihilation of the species," he added. "Yes, we're living in a time of dread, but I have a little bit more hope that this may just be one in a long series of things that we will have to deal with. And hopefully we will. I don't know how it's going to be dealt with, but people much smarter than me are working on it.”

Running alongside the questions that viewers will have about the morality of a system like VIXAL, which capitalises on angst, and what it is really capable of, is Alex himself.

The question 'Who is Alex Hoffman?' sits at the very centre of this narrative and is posited on a number of occasions by various characters. In the first two episodes that were made available for review, it's impossible to draw a clear conclusion.

"I read him with a more sympathetic view than I think most people would because he's a character I’m playing," said Hartnett, echoing what many actors will tell you about finding redeemable or relatable traits in an effort to access the person they're portraying.

"I see Alex as someone who is in the same vein as Dr Frankenstein, someone who is obsessed with the question of how and has never considered the question of why. I don't think of him as an evil person, but if you don't consider how what you're doing is affecting other people, it can end up creating very bad consequences, and thereby making you a villain."

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In the opening episode, Alex is attacked in his home in the middle of the night by an intruder who somehow circumnavigates the supposedly impenetrable security system. Following a number of other unexplained incidents, he is convinced that the attack was not an isolated incident, but part of wider ploy to destroy him. But we doubt his claims, as do those around him who are concerned that they are witnessing his rapid and unfaltering descent into madness.

Hartnett compared Alex to the figure of Cassandra in Greek mythology, who was cursed by Apollo. He gave her the ability to see the future, but no one believed a word that she said.

"One day you could be at the top of the world and the next minute, you could be locked up and fighting for your life," he explained. "It is terrifying. It does tap into that existential dread, but it also taps into the dread of losing one's mind and that freaks me out, maybe more so. It could happen to anyone."

Every project Hartnett's undertaken has had a distinct set of challenges but the demands of this job far exceeded that of his previous work. Inevitably, COVID restrictions played their part, but it was Alex's heightened emotional state that tested his limits.

"From an endurance standpoint, this is one of the hardest jobs, if not the hardest job I've ever been involved in," he admitted. "When I read it I thought, 'Okay, this is a guy having a nervous breakdown over the course of a day.' Even though it was a short shoot, it was still a long time to be going through a nervous breakdown. I thought, 'How am I going to pull this off? How am I going to keep it on this sine curve that makes sense to people?'

"And I hope I pulled it off. I hope it works. That challenge was scary enough to me that I had to run towards it. I had to do this."

The Fear Index is available to watch on Sky Atlantic and NOW. If you’re looking for something else to watch tonight, check out our TV Guide. and keep up to date with all of the latest news over at our Drama hub.

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