Alex Gibney was born in New York City in 1953 and educated at Yale and UCLA film school. He was 52 when he scored his first major success as a documentary film-maker with Enron: The Smartest Guys in the Room (2005). Three years later, he won a best documentary Oscar with Taxi to the Dark Side. Since then, he has been hugely productive, turning out films about political sex scandals (Client 9), WikiLeaks (We Steal Secrets), doped-up cyclists (The Armstrong Lie) and Scientology (Going Clear). The theme of high-level corruption, which runs throughout his work, lies at the heart of Dirty Money, a six-part series he has produced for Netflix.

What drew you to these particular stories?

We were looking for stories in which the characters seemed larger than life and in those stories you find the larger themes. With people like [VW exec] Stuart Johnson, whose deposition we showed in Hard NOx [the first episode of Dirty Money, which Gibney also directed], it was instructive that he felt the need to tell the truth. It was the same on the Enron film: people wanted to unburden themselves. They all remembered a kind of slow corruption, what they called a tugging in the gut when they felt they might be doing something wrong. But your boss thinks it’s OK, so you go ahead, making one corrupt compromise after another, until you realise the line you weren’t supposed to cross disappeared some time ago.

Can you empathise with these people?

You have to. Otherwise, you inhabit a view of the world that I don’t believe in, which is that there are good people and bad people, whereas I believe we’re all a mixture of both. When I do interviews, my goal is not a kind of “gotcha” moment, it’s to understand the perspective of the people I’m talking to. Empathy is terribly important.

You were one of the people duped by VW into believing its diesel cars were clean. Do you find it useful as a film-maker to have a connection to the story you’re telling?

Not always. In this case it may have been born out of frustration. I was having a hard time penetrating VW, so I decided to make it more of a personal journey. I really did think that I’d bought this wonderful car that was so fun to drive, had great mileage, was so clean – until I realised, oh no, all the plants are dying as I drive by.

The final film in the series focuses on Trump, who has been covered endlessly over the past couple of years. What more was there to add?

The essence of Trump’s appeal was that he’s a great businessman, so therefore he’ll be a great president. We thought, OK then, let’s take a focused look at what he was like as a businessman.

Not so great, it turns out…

He was an absolutely terrible businessman. Every business he touched withered and died and he would always leave someone else holding the bag. You look at the trail of slime he left behind and just shake your head and wonder.

Why do you think people are still buying into him?

It’s something I dealt with in my film about Scientology: some people just have the need to believe in Trump. They come to feel that he represents part of their character. No matter how much evidence you present to them about what a bad guy this is, they don’t want to hear it, because somehow an attack on Trump is an attack on them.

Can you imagine him staying the course?

Yes I can. A similar thing happened in Russia when Putin rose to power: everybody mocked him as some small apparatchik who wasn’t going to stand the test of time. But power has a way of solidifying.

Given the focus of your work, do you exist in a state of constant outrage?

You can’t – you’d go crazy. I spend a lot of time trying to find other outlets. I dig into music. I’m a fanatical tennis player. I love to watch sports. And my wife and I are getting into mindfulness meditation. You have to find some reason for optimism about the human condition, otherwise you end up being that bitter person drooling in the corner talking about how we’ve all been screwed.

I see the opioid crisis in the US more as a crime story. And I find the psychology very interesting Alex Gibney

It must be a good time to be making investigative documentaries – there’s so much going on…

There is a hell of a lot going on, but there’s also an intense interest in and affection for documentaries, which was utterly missing when I was starting out 30 years ago. Audiences have come to appreciate films that don’t have actors in them.

What stories are catching your eye at the moment?

The opioid crisis in the US. There’s been a lot of hand-wringing about it, as if it’s some kind of natural disaster. I see it more as a crime story. And I find the psychology very interesting. People like the Sacklers [the family who made billions from OxyContin] have a hard time understanding why anybody should consider them the bad guys – after all, they were just trying to make a buck.

Have you been following the #MeToo movement? Any thoughts?

I think it’s a hugely important moment in history. As a white man, I think it’s also my moment to listen rather than proclaim. But you realise how pervasive the problem is. I was reading some correspondence of my dad’s, when he was in journalism, and it betrayed the worst kind of male supremacy and sexism. It was baked into the environment and that’s a terrible burden for 50% of the world to bear.

Do you ever read for pure pleasure or are you always looking for stories?

A lot of reading I do is pretty targeted – skimming a book for this or that. But I’m going on a short vacation soon and I’m bringing along Americanah by Chimamanda Ngozi Adichie. Also, my friend Lawrence Wright has a new book on Texas, which I’m dying to read.

You said you’re a fanatical tennis player. Are you any good?

In my mind I am. I wouldn’t say anybody on the tour would be shaking in their boots. But I’m good enough to at least hit the ball with most people.

Dirty Money is available now on Netflix