I know that Invasion of the Body Snatchers has interesting moral themes and lots of subtext about communism, premarital sex, conformity, and more. One could write many essays on the film’s exploration of those subjects (and people have). That being said, I want to talk about form here. I think that Invasion of the Body Snatchers is a fascinating exploration of genre. It has qualities that fit into the classic horror genre, science fiction, and also notable traces of film noir. However, it also has elements that keep it from totally fitting into any one of those genres; it is an amalgamation of all three.
American culture went through a big shift in the 1940s and 50s. World War II had changed people. It was a time of cynicism, mistrust, and an awareness of the dark side of ourselves. That was reflected in American cinema. Darker themes, morally complex protagonists, and edgier visuals abounded in movies.
The 1950s was a Golden Age for American B-level horror. Invasion of the Body Snatchers uses many of the characteristics of these horror films. It is a monster movie, though not a typical one. Instead of a puppet, or a man in a costume, the monsters look just like other people. Invasion was a topic that was not foreign to the 1956 audience. They were constantly worried about communist infiltration, and that fear is reflected in the paranoia and heightening desperation of Invasion’s lead characters.
In B horror movies, especially monster movies, humans are the good guys. We are the force for peace and goodness, as opposed to the evil or chaotic monsters. People liked to forget their guilt about the United States dropping atom bombs on Japan. Invasion allows it's human protagonist, Dr. Miles Bennell, to be the one voice of love and emotion. Invasion definitely scared audiences, and shared many things in common with it's contemporary horror films.
The most obvious reason to classify this movie as a science fiction film is that it's about aliens. Aliens are one of the most recognizable hallmarks of sci-fi. There is also a body-switching element because of these extra-terrestrial organisms. Sci-fi B movies in the 50s frequently focused on social/political issues and the human condition, which Invasion of the Body Snatchers definitely did.
In sci-fi movies, there is often a visual clash between unfamiliar and conventional images. I think that the use of Dutch angles in this movie is sometimes to serve this purpose. You have familiar composition image- triangles, following the rule of thirds, etc.- but it is off-kilter by using a shot where the camera is turned at an angle. Don Siegel also uses a lot of low angle shots, and I think part of the reason he chose them was so that we would see our familiar protagonist in a weird, different way. Science Fiction is probably the category Invasion fits in the best.
The last genre Invasion of the Body Snatchers fits into is the iconic film noir. The most obvious reason this movie is recognizable as being noir-y is the visuals. It is high contrast black and white, sometimes using long shadows and partially obstructed light (like through blinds).
One of the quintessential characters of film noir is the femme fatale. Doctor Bennell’s sweetheart Becky matches much of the femme fatale criteria. She matches the stylistic requirements in her hair and wardrobe. Although she brushes off the doctor's attempts to sexually engage with her, she still holds a sort of sexual charm over him. Another element of the femme fatale is the male protagonist’s desire to control her, which is definitely super present in Invasion. When the doctor finally loses control of Becky at the end of the film, when she succumbs to the aliens, she becomes the nefarious temptress typical of the femme fatale. As Barry Keith Grant said is his BFI Film Classics book about Invasion of the Body Snatchers: “Becky’s refusal to be seduced by Miles’s kiss makes her nothing
less than a monstrous embodiment of the more independent woman in postwar
America”.
less than a monstrous embodiment of the more independent woman in postwar
America”.
While Invasion does explore the dark side of society, one of the qualities abundant in film noir is a protagonist who is a good man who gives in to temptation. But Dr. Bennell does not give in. Well, he is divorced and wants to sleep with Becky in the first place, which makes him a little edgy to start out with, but he never give a up his humanity.
I think that Invasion of the Body Snatchers is one of the most interesting genre bending movies of the 20th century. It is a product of it's society, and explored lots of weird, interesting themes, and I think it's use of the horror, science fiction, and noir genres allows it to delve into those themes in a unique way.