Anyone seen Dark City? If you haven’t, this might ruin it for you.

If so, you’ll know what happened. Aliens abducted a few humans and put them in an artificial city in space for research. Aliens can alter reality as they see fit and inject humans with memories to see their reactions. What if your memory was injected into your brain? You would not have any awareness of it because your functioning is so hopelessly dependent on memory.

Shell Beach was the city that everyone was from, at least in their memories. No one remembered clearly what happened in their past. Can you clearly recall something that happened 10 years ago? If you can’t, it’s likely your memory could be fake, according to the movie.