The premise is slightly incohesive and incoherent. Clement has set an overly ambitious task for himself with Exhumed--in his words, to create a "(postmodernist) critique of postmodernism" combined with an homage ("ripping off" as he calls it) to various kinds of genre films. Despite two good segments, the whole doesn't quite make it.
That's a shame, because both The Forest of Death and Last Rumble rise above--sometimes far above--their super-low-budget limitations. The problem is that Shadow of Tomorrow is awful, and the attempt at an overarching sci-fi horror story never rises above being gobbledy-gook. It's so nonsensical (in a bad way) that it begins to make Donnie Darko (2001) look like the masterpiece that it's not. Clement should have instead made two films--feature length versions of segments 1 and 3, and tossed the Shadow of Tomorrow stuff into the garbage. Then he would have had two 8s instead of one 6, which is equivalent to the letter grade of "D".
Let's talk about what's wrong with Shadow of Tomorrow first, since it's basically what ruins the film. In the director's commentary, which is shared with producer/actor/costume-designer Claire Westby, Westby notes a criticism she encountered about this segment. The critic complained that they were "trying" to make it just like a film noir. Westby countered with, "That's the point!" I think she may be misreading the word "trying". Trying doesn't necessarily mean succeeding.
Many if not most film noirs were quality films, with fine performances, interesting stories, intriguing scripts, great cinematography, lighting, editing, and so on. Sure there were a lot of unusual film noir actors, with quirky dispositions and deliveries--like Humphrey Bogart, Peter Lorre, and James Cagney, but they weren't bad actors--far from it. The film noir segment of Exhumed is loaded with bad acting, a pointless story, banal dialogue, overdone lighting and bad editing.
Clement apparently instructed the cast to be "over-the-top", but over-the-top doesn't mean "deliver this generic and clichéd dialogue in the most stilted, amateurish way you can". If that's what film noir is to Clement and Westby, they're insulting film noir. To make matters worse, Clement and Westby spend a lot of this segment's commentary talking about trying to get period elements just right. Look, I don't care if a skirt hemline is the "right length" or if the radio is of the era and shown subtly or not. Work on creating a good story and dialogue while capturing quality performances. For all the putative period concern, the lighting in the segment, although interesting, is far too harsh to mimic a film noir. The contrasts were not that stark, or at least didn't appear so on film. Perhaps adaptations needed to be made for digital video. Also, despite the very brief Night of the Living Dead (1969)-like opening and the bad Dr. Frankenstein stuff in the end, this segment is not horror or sci-fi, and doesn't fit the tenor of the rest of the film. It doesn't help when the film noir stuff reappears at the end, either.
The problems with Exhumed's film noir are all the more curious in light of the two good segments. The Forest of Death genuinely captures the feel of a late 1960s/early-1970s kung fu horror film. It has a very interesting story and dialogue, pretty good acting, directing and editing, great martial arts work and fantastic special effects. Even though the story is a bit thin for a 90-minute film, it could have easily been expanded without adding much in the way of plot to make a fine film in the tradition of Master of the Flying Guillotine (1975), which has an even thinner plot but is still a masterpiece.
The Last Rumble segment may be even better. It's a bizarre concatenation of everything from Quadrophenia (1979) to Psychomania (1971), The Crazies (1973), Underworld (2003), Evil Dead II (1987), 12 Monkeys (1995), Hellboy (2004), Zombi Holocaust (1980), "Buffy the Vampire Slayer" (1997), "Angel" (1999), Frankenstein (1931) and even the Santo films (beginning with Santo vs. The Infernal Men in 1958). We get motorcycle riding vampire and Fu-Manchu-eyebrowed werewolf gangs in a crazy, surrealistic plot that includes a great vampire and werewolf lesbian scene and lots of well done graphic carnage. The gobbledy-gook almost works in this section, as its consistent with the bizarre tenor of the rest of the material--Psychomania is probably the best comparison for this. Only in this section did Clement achieve a successful wide-ranging genre film pastiche. In Last Rumble, "over-the-top" really is over-the-top, and the result is something that almost spoofs its sources while still respecting them. The sole limitations here are budget-oriented.
Exhumed is not really a critique of postmodernism, and isn't really postmodernist. Postmodernism isn't a cannibalization of self. It's not an exhumation of material. Clement is mistaking postmodernism's particular kinds of self-reference for (necrophilic?) cannibalism. Those are two different ideas, and even self-reference isn't sufficient (or necessary, for that matter) for postmodernism. To be postmodernist, self-reference would have to be in service of pulling the rug out from "truth", or in the case of films, breaking levels of removal--various fictional levels versus reality, theatrical conceits in films, and so on. Instead, Exhumed is more like honest and occasionally sophisticated low-budget hackwork. Sometimes it's successful, but overall it has problems.