“Initially, it was felt that I had no feature experience,” Alex Parkinson, writer and director of survival thriller Last Breath, told an RTS audience at the Bristol Everyman. Then he added: “This is true."

Parkinson was not the first pick to direct the feature, despite having directed the 2019 Netflix feature documentary on which the film is based. “They took it to a different director... a very well-known director, who I will not name,” he said. That Hollywood director then stepped away from the project, giving Parkinson the chance to pitch.

Last Breath tells the incredible story of a deep-sea diver stranded on the ocean floor and his crew’s attempts to rescue him. “The original script was really good, but it was very Hollywoodised, so it was, like, oil rigs blowing up, people being washed overboard,” said Parkinson.

“My vision for it was to bring more authenticity and realism, because the story is so amazing how it is. I didn’t really need to make anything up for it.”

Parkinson pitched his vision of authenticity and it earned him the gig. As it turned out, his experience of directing the documentary and working closely with its subjects was invaluable when it came to casting. “It massively helped [knowing the documentary’s subjects] because I think the three – the triumvirate in the bell, Woody [Harrelson], Simu [Liu] and Finn [Cole] – have the essence of who those real people are, and that’s why I cast them.”

When production came around, the reality of directing a feature film set in. Parkinson recalled: “The first time I had ever been on a working film set was the first day of shooting –and I was directing Woody, Simu and Finn!”

The day before shooting, he realised: “I don’t even know what I’m supposed to do on set. Do I call action? Do I call cut? I had to call up my DoP on that Sunday and go: ‘This is a bit embarrassing, but could you actually talk me through what I’m supposed to say and do?’”

Parkinson soon got to grips with his role but he had the added difficulty of directing actors who were underwater. “It’s very complicated to do, ruinously expensive and extremely time-consuming,” he said, recalling shooting in a huge water tank in Malta.

He directed from a pontoon above, and had to pass messages through dive supervisors to communicate with the actors. The water tank had no roof so they had to shoot at night to avoid daylight.

Meticulous planning was essential, Parkinson explained: “Every evening as the sun was setting, we’d turn up. We would have this model and a set, and I’d walk through with these Lego men.”

As Parkinson spoke to the RTS audience, one factor that continually surfaced was the goodwill behind the film. “The documentary was a great calling card,” he said. “We had this goodwill and spirit, and people doing everything they could for the film because they loved the documentary.”

Parkinson reflected on being at the Everyman for the screening, experiencing a full audience watching his debut feature, and all on the edge of their seats.

“The biggest pleasure is sitting at the back there and feeling people respond to the film. That’s the best thing about it. That’s why you do it, really, isn’t it? Isn’t that what we all do it for, to feel people respond to it?”