Dark City is probably the most entertaining film we've watched in class so far. The way the director has used Film Noir techniques to show a sci-fi plot is very interesting. The best example of this is that the entire movie is very dark, yet that aspect is actually expained as being due to the aliens.
The most obvious theme in this film is We Have No Control Over Our Lives.
There's not a single character in the film who is able to control their fate in the direction they would like. Murdoch can't remember who is hem, get to Shell Beach, or control the abilities he has, so he's constantly searching for the answers he wants. His 'wife' is trying to get him back and figure out if he's a killer. The Doctor is being manipulated by the aliens to do their work on the humans. And, even the aliens themselves are trying to gain control of their lives through the humans. The whole purpose of this "city" in the movie is for the aliens to find an answer to prevent the extinction of their species.
This theme is portrayed several times through the symbolism of the maze. Dr. Schreber is first shown toying with mice in a lab maze, and this image is mirrored later with the wide shot of the entire city's labyrinth design. Of course, this leads us to the idea that all the characters lives are being controlled by something larger.
Mr. Bennett mentioned in class when we started watching Asphalt Jungle, that all film noir films deal with characters who have siutations much bigger than themselves. So, it's appropriate that the theme of a modern Film Noir-influenced film like Dark City should be the lack of Control Over our Fates.