It's ingenious: Daniel Radcliffe on how his character 'Escape(s) from Pretoria' Central Prison

SPOILER ALERT! This article contains spoilers for the film Escape from Pretoria.

In 1987 Tim Jenkin published Escape from Pretoria, a memoir of his anti-apartheid activism, arrest by the security police, imprisonment and sensational escape in 1979. He escaped with fellow activists Stephen Lee and Alex Moumbaris. Jenkin says that he'd always thought his book was "good movie material" and he wasn't wrong.

Soon after its publication, the first attempt to film it began to look successful in 1988, but in the darkest days of apartheid, Jenkin firmly believed that the film needed to be political, and the producers wanted to cut out all the politics.

Since then, every five years Jenkin signed contracts for the option to adapt his book to screen but each time circumstances seemed to be against him. That was until in 2017, when, at his second attempt, producer Mark Blaney managed to get the project off the ground, thanks to a script by director Francis Annan.

It also didn't hurt that former Harry Potter star Daniel Radcliffe was attached to the project. For Jenkin that was the sign that this time the film would get made, after all.

Annan, a British television and theatre director, thought the book was made to be a movie. He said that in searching for a story to make his major feature debut he was looking for something familiar but also unique.

"This film is a prison escape movie, which is slightly different from a prison movie. They also don't just dig a tunnel or bop a guard over the head and run - they make something to open their cell door. I'd never seen that before. They were also Caucasian, middle-class men in the '70s who could have had a job in a bank, for instance, but decided to do this instead. In prison break stories you don't usually tend to have true-life characters who are virtuous and not criminals."

When he was approached to play Jenkin, Radcliffe says he was struck by this thought: "It's crazy that I've never heard this story before. It's such an amazing, ingenious escape and the fact that it was pulled off so elegantly and beautifully - it deserves to be in the cannon of great prison escape stories. As an actor, when you get a chance to be a part of spreading a story you feel is really valuable to a wider audience, it's what you live for."

Most of the action of the film takes place within the walls of Pretoria Central Prison, and could have theoretically been shot anywhere, but there are opening scenes during which Jenkin and Lee conduct their underground work as pamphlet bombers, and these are set on the streets of SA.

Annan intended to shoot the entire film in SA but due to clashes between the timelines of local film production facilities and the production's schedule, it became necessary to look elsewhere to shoot.

Annan needed to find a location that had similar geography and architecture to 1970s SA. He remembered the 1980 Bruce Beresford film Breaker Morant about the Boer War, which was shot in Adelaide in South Australia. The city, complete with jacaranda trees, was briefly transformed into apartheid-era Johannesburg.

As for Jenkin, he's pretty happy with Radcliffe's portrayal of his younger self, especially in the prison scenes. On screen, as in the book, there's not an awful lot of dialogue in these scenes.

"Daniel rolls on the bed from the pain and the fear and the stress of it and says the odd word here and there. That was my character and that was the character he tried to get across in the film."

Radcliffe admits that the thought of so many scenes in which so little happens and so much needs to be expressed was initially daunting, but he acknowledges the skill of his director.

"He showed me a film before we shot called A Man Escaped, much of which was shot in close-ups. A lot of information is communicated in those close-ups. I realised that I didn't have to do much, that the combination between how Francis shot and how I reacted would tell the story."

Jenkin is philosophical about what he hopes audiences will take away from the story besides its historical and political specificity and it's prison escape thrills: "I wrote the book as a metaphor for life," he says.

"In that metaphor we're trapped in prisons, whether they're personal or on a bigger scale like global prisons, our world is falling apart. You get trapped inside a prison and how do you get out of it? From the starting point you can't see the route to the end, but you have to start somewhere. You try and open one door and then a second, and each time you reach a barrier the whole vista changes because you have a different perspective ... That's what we did. We didn't really have a plan until the very end, when we realised that we could make a key for any door in the prison. We could do anything, go anywhere, we had full rein over this prison. Only then did our plan turn to what seemed impossible: opening the front door of the prison and walking out."

He adds, "The front door required some forcefulness at the end, [but when] you reach that final barrier you get a feeling of progress. You've accessed freedom, whatever that freedom is. Of course, you might have to change your plan at that last moment and do what you have to do."

• 'Escape from Pretoria' will next screen on TNT DStv Channel 137 on July 8 at 16h37 and at regular intervals throughout July and August.