Courtesy of STUDIOCANAL

Adapted from Guy Gibson's own book Enemy Coast Ahead, Michael Anderson's 1954 docudrama captures the tension and bravery of this audacious raid on the centre of Nazi Germany's industrial complex, and the quintessentially English combination of inventiveness and dogged determination. Split into two distinct sections, it deals first with the fraught, but ultimately successful development of a new weapon. The second and pacier section deals with the mission itself, and its associated costs for the enemy and for the British airmen.

Anderson had made his name as an assistant director, and had directed only a few small features before being offered The Dam Busters. With key actors in place, he spent two years researching the story and the principal characters. This approach explains the documentary feel of much of the film, especially in the detail of the bureaucratic obstacles to Barnes Wallis's plan.

The decision was made to shoot the film in black and white, in order to allow the integration of original footage of the bomb trials, and to preserve a 'gritty', documentary-style reality. By good fortune, the Ruhr was in flood at the time of shooting, allowing the crew to film the flooded towns and valleys and incorporate this into the closing scenes.

The model work was completed prior to principal shooting to ensure the climax of the film was right, and to allow the flight scenes to be built around this. Five Lancaster bombers had to be rebuilt for the film, with a special studio aircraft mounted on a mechanism designed to allow it to bank and tilt.

The actual raid occupies surprisingly little screen time, with Barnes Wallis, his invention and his determined pursuit of the idea making up the bulk of the film. Anderson's clear intention is to celebrate the unsung heroes of the wartime period, and to highlight one facet of Britain's national identity. In demonstrating the way in which Barnes Wallis's inventions are routinely confronted by bureaucratic negativity, Anderson also passes critical comment on Britain's dismal tendency to stifle genius.

It is testament to Anderson's authoritative, quiet guidance that the performances are largely realistic, and multi-dimensional. The end of the film might, in other hands, be an opportunity for jingoistic flag-waving, but instead Anderson emphasises the human cost of war without falling into sentimentality.

Freddie Gaffney

Click titles to see or read more