Fear of nuclear war undercut much of life during the 1960s as Cold War tensions mounted between global superpowers and perhaps nothing represents this sentiment better than a lesser-known and incredibly controversial film set in Kent. The War Game is a docu-drama commissioned for the BBC that, despite being made in 1965, would not be broadcast on television until 20 years later.

Deemed "too horrific for the medium of broadcasting" at the time, the production depicts a fictional nuclear war and its aftermath in grizzly detail from the perspective of a typical English city. Opening on a description of Britain's then nuclear deterrence policy of threatening would-be attackers with annihilation from the Royal Air Force's nuclear-armed V bombers, the pseudo-documentary then follows an escalation of global conflicts, prompting an all-out nuclear war.

In Kent, a one-megaton nuclear missile overshoots Manston Airfield and airbursts six miles from Canterbury, eviscerating the historic city and its surroundings. The film examines the carnage that ensues, showing a defence worker and a boy being struck by the heatwave, causing their eyeballs to melt while a nearby house is ravaged by fire before being knocked down by the subsequent shockwave.

Elsewhere, another boy suffers flash blindness from an explosion 27 miles away. Over in Medway, an airburst bathes Rochester in fire, nearly wiping the town from the face of the earth in mere moments.

We see Kent's emergency services buckling under the weight of the situation they now face as each remaining doctor struggles with the ever-growing volume of casualties. Responders are shown leaving the worst affected to die, while some police shoot those in particularly awful states as a form of mercy killing.

Later in the film, radiation sickness is explored as women are left infertile while others are left permanently scarred by third-degree. With such gruesome scenes as these making up a substantial portion of the 48-minute runtime, it becomes clear why the film was dubbed "horrific".

Shoots took place in a number of major Kent towns, including Tonbridge, Gravesend and Chatham. A great deal of filming took place at The Grand Shaft in Western Heights, Dover as the semi-destroyed barracks served as a perfect backdrop for many of the post-strike scenes.

Writer, director and producer Peter Watkins put together The War Game on a small budget of an estimated £7,000 with a cast of around 350 people comprising amateurs and non-actors. Originally slotted for a BBC 1 screening date of October 6 1965, The War Game was ultimately shelved from the television schedule, with much discourse over the decades that have followed to determine who was actually behind the decision.

At the time, the BBC said in a statement: "The BBC has decided that it will not broadcast The War Game, a film on the effects of nuclear war in Britain, produced by Peter Watkins. This is the BBC's own decision. It has been taken after a good deal of thought and discussion but not as a result of outside pressure of any kind."

However, it is known that the production caused dismay with the then ruling Labour government and Prime Minister Harold Wilson which it is widely believed contributed to the film being withheld from broadcast. In 2015, Scottish academic John Cook, a professor at Glasgow Caledonian University, got hold of previously classified Cabinet Office papers thanks to a Freedom of Information request which contained details on a lunch between the then head of the BBC Sir Hugh Greene and a senior minister.

The files showed that it had been agreed the BBC would take ownership for the decision not to air The War Game if that were the ultimate result. Speaking at the time, John Cook said: "Examining the files, I was surprised at the level of scrutiny the government paid to the film and how explicit discussions were to suppress it.

"Politicians, not just civil servants, were involved, including then Prime Minister Harold Wilson. None of the discussions concerned preserving the independence of the corporation, but rather how to find a way to suppress the film without implicating the government or embarrassing the BBC."

The War Game would then premiere in April 1966 at the National Film Theatre in London where it ran until May 3 and was subsequently shown at several other film festivals, including Venice where it won the Special Prize. Despite its fictitious narrative, the film won the Academy Award for Best Documentary Feature in 1967.

Innovative for its time, Watkins weaves harrowing scenes of catastrophe between fictional interviews with officials such as doctors and psychiatrists giving insight into the mental health toll a nuclear attack would have on the population. In July 1985, the film was finally televised in Great Britain in the week prior to the 40th anniversary of the Hiroshima bombing.

Then in 2013, the BBC invited a number of those who took part in the filming and creation of the docu-drama to a special screening held within a Gravesend nuclear war bunker. The War Game has also since seen a physical release on both DVD and Blu-Ray and is available for digital purchase through Amazon and Apple