|Neff hides in the back of the car
The film is bookended by insurance salesman Walter Neff (Fred MacMurray), narrating a confession of sorts into a dictaphone, for his colleague Keyes to find. He has committed a murder, and intends to get the story straight. The body of the film, then, is told in flashback. Despite the fact that we already know the murder will be committed successfully, the film is incredibly tense, the characters' plotting constantly frustrated or threatened with discovery. We know the murder will happen, and we want it to happen, and fear for the two conspirators.
|Phyllis and Neff, after the event.
The murder itself isn't shown. The shot cuts away to Phyllis's reaction, and the death is left to the viewer's imagination. Indeed, we never even see the body, though Phyllis and Neff manhandle it into position for discovery. At the point of death, Mr Diedrichson disappears entirely from the film's pictures, and what could be schlocky or grizzly is allowed to be functional, tense and dramatic, the emphasis on the murderers, not on the body.
|The magnificent Edward G. Robinson
Robinson gives an excellent character performance - charismatic, energetic and contemplative, his whole body serving his dialogue. The whole film is worth watching for his performance (though even without it the film would be worth watching, its direction exquisite, its dialogue fast, witty, American poetry). Keyes is a very close friend to Neff, and matches or exceeds his intelligence, so the question soon becomes, not 'will they get away with the murder', but 'how can they hide the truth from Keyes'. Eventually, of course, the question is why Neff ends up confessing into a dictaphone.
I think you should give this film your time and attention, so I've been careful not to spoil anything that isn't established in the first five minutes. This was one of the most enjoyable viewing experiences of the project so far (which, by the way, is roughly half-way through), and I hope you find it as exciting as I did.
P.S. Since I'm currently going through decade by decade, I knew the next update had to be from the fifties. It was nearly 'Touch of Evil' (1958), but that would give us two films noir in a row, so I instead went with something entirely different, 'The Seventh Voyage of Sinbad' (also 1958).
It's a very good film. You should watch it some time.