Lance Armstrong’s story is an implausible, unbelievable, incredible, but none of those adjectives would be applicable if the following wasn’t: it’s true. In The Armstrong Lie, Gibney admits to rooting for the shamed cyclist, before discovering – along with the rest of the world – that he’d been cheating.

Lance ArmstrongLance Armstrong tells his side in The Armstrong Lie

Famed for his insightful, thought-provoking documentaries that explore some of the biggest happenings in culture, sport, politics and crime – even though those spectrums often collide – the route that lead Gibney to his Armstrong piece wasn’t typical.

"He lied to me. Straight to my face. All throughout 2009," Gibney says in the trailer. "This is not a story about doping. It's a story about power. And the story became hanging on to that power." One gets the impression Gibney’s story is being told alongside Armstrong’s, with obvious emphasis on the latter; the subject matter.

Watch the trailer for The Armstrong Lie here

Armstrong publicly admitted to the doping in an interview with Oprah Winfrey in January 2013. He did, however, deny that he was doping in 2009-10 saying the last time he “crossed the line” was back in 2005.

Engaged in the filming of the cyclist’s comeback following his diagnosis and subsequent treatment for cancer, Gibney was covering a time in Armstrong’s life plagued by accusation and media coverage. He maintained, throughout, that he had not taken steroids, blaming a positive test result on a cream he had administered.

Lance Armstrong documentaryFans and critics alike will want to see what this man has to say

But when the news broke that Armstrong’s career had been fuelled by steroids, stripping all of his world and regional titles and medals away from him, the sporting world stood still. Gibney didn’t; feeling like he was owed an explanation – an apology, perhaps – the filmmaker set about finishing off his documentary. And so the work-in-progress style doc was completed.

In it, we finally get an explanation – he “finally sets the record straight” - from Amrstrong, who sits down with Gibney to talk through the lies and a career of ill-gotten sporting achievements. The film is out on October 8th at theHamptons International Film Festival and gains a wider - but still limited - release on November 9th.

Lance Armstrong cyclingAs ever, Gibey's work is masterfully shot