They Came Back is an odd little piece of cinema with no greater meaning, which I think probably threw a lot of watchers for a loop. There are no conclusions to be drawn, thematically or narratively, so what you get is a ninety minute day-in-the-life hypothetical as approached through the viewpoints of several people. We get some good depictions of the emotional impact that this resurrection event has on the bereaved, and overall the film did a fine job of actually making me feel what it's like to be a zombie. It's stultifying, but in light of the film's long and leisurely shots and its creeping music, to say nothing of the insulated suburbia we get so many glimpses of, this was clearly the director's intention.
I think that the movie's greatest shortfalling is its mechanical inconsistency. It is a magical realism piece, which is perfectly okay, but the movie's insistence on exploring the "why?" of the film makes the omission of the "how?" all the more glaring. I mean, why not a scene where the scientists and governmental figures in charge ruminate on what's actually brought the dead back to life? We are offered plenty of possible explanations regarding their unusual behaviors, their discordant speech and their routines, and several scenes are set aside to discuss the logistics of accommodating 13,000 extra people. It's not necessarily that I expect or need this question to be answered, but hearing the characters tackle the movie's greatest mystery would have added to the "realism" part of this film. Furthermore, there's a plot development toward the end that doesn't make an ounce of sense in any regard.
*minor spoilers ahead*
The zombies are able to pull off a rather complex covert operation without arousing any sort of suspicion; I find it strange that they would be able to pull this off undetected, especially with the level of scrutiny that the humans apply to them. This may seem nit-picky, but it's a fairly severe issue that is quite apparent if you give what's happening a few seconds of thought. As with the rest of They Came Back, the ending will please a few but frustrate others; in keeping with the rest of the movie's inexplicable bizarreness, I found it appropriate. Pound for pound, I won't be surprised if you don't like it, but I got a kick out of its vague creepiness and human insights. Not recommended to those looking for a definite plot, or any plot at all, really.