I watched both movies earlier this week. Coincidentally both were released in 1998 and tackle similar themes of controlled populations, though the narratives are in some ways asymmetric mirrored images of each other.
In The Truman Show we have a character manipulated by an entire island acting out day to day life while the rest of the world watches his story from birth to mid marriage ennui. Actually the gullible consumers of the world are rooting for Truman (played by Jim Carey) because like him they are easily manipulated and trapped though they don't quite realise it is their attention that is for sale as the product placement medley makes clear in the first clip.
Dark City's premise is that an entire city is being energetically devoured or fed upon (in much the same way as cock fighters get off by observing the fighting of animals) by an Archontic alien/astral entity/men in black force who can freeze the entire population at a moments notice and change circumstances including a persons entire memory and personality.
Echoing that mirrored narrative I mentioned at the outset, we see that Truman's life is a never ending beautiful day wearily acted out in a simulacrum of happiness, social cohesion and veneers of harmony whereas in Dark City the themes are tackled through film noir sets, nihilism and nights that never end and a sun never rises.
It's extraordinary to me that the Truman Show eclipsed the entire constructed reality TV trend. As if Hollywood was preparing populations for TV ideas of constant surveillance entertainment and the notion of being closely observed by all pervasive and discreet technology.
Astro theologists may have picked up that it's the Sirius star light that comes crashing down in the beginning of the movie giving a brief clue to Truman and us of the observational process not forgetting its Orion's belt alignment I've been talking about from time to time.