This film recounts an historical incident in which about two dozen British Lancasters delivered specially designed bombs that destroyed two important dams supplying water and hydroelectric power to the industrial area of the Ruhr. It sticks fairly close to the facts and it doesn't meander about. No rivalries over women in the pub. No women at all, practically. There is one brawl between fliers but it's a good-natured free-for-all in which everyone wrestles and laughs and no one throws a punch. The whole film is constructed around that cheerful exuberance. Everyone is anxious to take on this dangerous job. Nobody weeps. And when the bomb's designer hears of the mission's success, he grins widely and flaps his arms against his side as others congratulate him. And that's it.
The film is really divided into two parts. In the first, we follow the man who designed the plan and the bomb to go with it, Barnes Wallace, played as an abstracted but determined boffin. (He also designed a couple of bombers.) In order to hit the dam and sink to the proper depth before exploding, the bomb must be dropped from 60 feet at a designated speed and a specified distance from the target -- and at night, too. The film tells us that much but leaves out the fact that the bomb had to have a reverse spin of 500 rpm at the time of release, so the project was still more challenging. It's almost inconceivable that such a mission could be pulled off.
In the second part of the film, Guy Gibson (Richard Todd) and his fliers train to the point of exhaustion before undertaking the mission, which is about as deadly as can be imagined. Fifty-six men failed to return. (Gibson was killed on a later mission.) The climactic action scenes are well done, if the events themselves are a little turgid. At times it's a little difficult to follow what's happening and who exactly is involved, though the general sense gets through. Two of the three target dams were destroyed, flooding the valleys downstream, but the dams were up and running again about five weeks later. More than 1200 people were killed on the ground, mainly allied POWs. Spectacular raids often make for good drama but the results, if the missions are successful, are often temporary. (Eg., Ploesti.) The enemy has a habit of fixing things that are damaged. It seems, depending on the particular targets, that you either have to pulverize them or attack them repeatedly, and even then the enemy adapts.
None of this, these nettles of realism, can possibly reflect on the courage of Gibson and his colleagues. The decorations they earned were more than deserved. And none of this should make a viewer hesitate before seeing the movie. It's done in a grand style, though, to be sure, the special effects are of the period.
The Avro Lancaster, by the way, may have been the finest heavy bomber of the war. It wasn't particularly fast, it was lightly armed, and it was as ugly as sin, but it carried an enormous bomb load, was versatile, and handled like a fighter. A test pilot managed to put one through a barrel roll.
The acting doesn't really need too much comment. Michael Redgrave is very good. Richard Todd marches around and makes up-beat comments like a military man, which he was. A good war movie, and recommended.